Thermoplastic elastomer, use thereof, and process for producing the same

ABSTRACT

The present invention presents a thermoplastic elastomer that exhibits superior moisture permeability, excellent flexibility and mechanical properties at a high temperature, particularly settling resistance at a high temperature, and excellent moisture permeability. The thermoplastic elastomer includes, as a constituting unit, a polyether component (A) and a polyester component (B), wherein the polyether component (A) includes poly-oxyalkylene groups (—C n H 2n O—) having a carbon/oxygen atomic ratio in a range from 2.0 to 2.5, the polyester component (B) has a number-average molecular weight in a range from 500 to 10,000, the thermoplastic elastomer has a content of polyether component (A) in a range from 50 to 95 weight %, and the thermoplastic elastomer has a glass transition temperature of not more than −20° C.

This application is a 371 of PCT/JP00/06812 filed Sep. 29, 2000.

BACKGROUND OF THE INVENTION

1. Technical Field

The present invention relates to a thermoplastic elastomer comprising apolyether component (A) as its constituting unit, and to a productionmethod thereof. The present invention also relates to a fiber made fromsaid thermoplastic elastomer possessing excellent water absorption andmoisture-releasing property, and to a fabric made from said fiber.

More particularly, the present invention relates to an elastomer sheetpossessing excellent moisture permeability and cut-off performance madefrom a thermoplastic elastomer comprising a polyether component (A) asits constituting unit, and to a production method thereof.

The present invention also relates to a moisture permeable waterproofingfabric possessing excellent moisture permeability and waterproofingproperty simultaneously, and to clothes, tents, and shoes that are madefrom said fabric.

The present invention also relates to a molded product, which isemployed in the fields of medical treatment, hygiene, orpharmaceuticals. More particularly the present invention relates to amolded product for medical use, for example, containers such as infusionbags or blood transfusion bags, and the like; tubes used for infusionset, blood transfusion system, or catheter; or injection-molding partssuch as stoppers thereof.

2. Background Art

In recent years the notion toward preservation of the environment hasbeen raised, and which results in accelerating replacement of existentraw materials with recyclable ones in various industrial fields. Withregard to the rubber materials, thermoplastic elastomers (TPE) have beenthe focus of attention for a long period, and are employed in the fieldof various industrial products for various applications.

Among them, thermoplastic polyester elastomers (TPEE) are known topossess excellent mechanical strength, heat resistance, abrasionresistance, and bending-fatigue resistance, and have been used in a wideindustrial field such as the field of automobiles.

The thermoplastic polyester elastomer (TPEE) is roughly classified intothe polyester-polyether type and the polyester—polyester type, theformer of which is the present mainstream.

Polyester-polyether elastomers are obtained from the ester-interchangereaction followed by the condensation reaction under vacuum using, forexample, dimethyl terephthalate, 1,4-butanediol, and poly-tetramethyleneglycol as the starting materials.

In more detail, they are multi-block copolymers made from the hardsegment comprising condensation product of 1,4-butanediol andterephthalic acid, and the soft segment comprising condensation productof polytetramethylene glycol and terephthalic acid.

Such thermoplastic polyester elastomers usually have high stiffnesscompared with ordinary rubber, and are devoid of flexibility. Inaddition, they exhibit large permanent compression strain under hightemperatures and large deformation, thus they are devoid of settlingresistance. These defects have long been expected of bettermodification.

In adding further flexibility to thermoplastic polyester elastomers, itis necessary to reduce the amount of hard segment component that takescharge of physical cross-linking. An existent technique such asdisclosed in Japanese Patent Publication for Laid-Open 88632/1990,however, decreased the block property of the hard segment componentcausing problems such as lowered melting point and inferior mechanicalstrength at high temperatures.

Concerning the settling resistance, as is disclosed in Japanese PatentPublication for Laid-Open 121699/1977, another technique which improvesthe settling resistance by raising the polymerization degree. But it hadits limitations, and compatibility of settling resistance andflexibility was difficult to obtain.

On the other hand in the field of sanitary products or fabrics, rawmaterials with excellent moisture permeability are the present focus ofattention. As is disclosed in Japanese Patent Publication for Laid-Open111847/1984, the moisture permeability may be improved by specifying thecomposition and the amount of soft segment.

Also, as is disclosed in Japanese Patent Publication for Laid-Open290714/1987, thermoplastic urethane elastomers are known to possessexcellent moisture permeability. However, the moisture permeability ofthese existent materials is still insufficient and a further improvementis desired. Besides, in the case of urethane resins made frompara-phenylene-diisocyanate, which is used very frequently, the productdiscolorates under the radiation of light. This also remains a point tobe improved.

There have been many assiduous investigations concerning alternative useof polyester resins instead of polyurethane resins for production ofcomposite sheets. Since polyester resins, however, usually show lowsolubility in various solvents compared with polyurethane resins, thereare the restrictions to the processing method in actual application. InJapanese Patent Publication for Laid-Open 311233/1996, a method ofapplying a solution of polyester elastomers on a base material withheating, followed by solidifying under cooling and wet-forming the filmto obtain a porous film is disclosed.

Fibers made from raw materials that have excellent water absorption andmoisture-releasing property are known to exhibit superior sweatabsorption as well as excellent treatment of sweat in, and to providefabrics having dry touch and are smooth.

In the past, polyurethane elastomer fibers have been used as theelastomer fibers. In recent years, however, new polyester elastomerfibers have been the focus of attention, which are made from the hardsegment comprising highly crystalline polyester such as polyethyleneterephthalate or poly-butylene terephthalate, and the soft segmentcomprising polyalkylene glycol such as polytetramethylene glycol.However, these materials are still hydrophobic, and accordingly showlimited moisture absorption in a fabric form. Thus it was impossible toprovide a fabric with dry touch.

As a raw material with excellent water absorption and moisture-releasingproperty, Japanese Patent Publication for Laid-Open 111847/1984discloses a ester elastomer having excellent water absorption andmoisture-releasing property, which is produced by specifying thecomposition and amount of the soft segment. Also Japanese PatentPublication for Laid-Open 290714/1987 discloses a novel thermoplasticurethane elastomer. All these products, however, exhibitedunsatisfactory moisture absorption and drying property.

The thermoplastic polyester elastomers are also known to be used forfilms or sheets. (see Japanese Patent Publication for Laid-Open133032/1982.) Such films or sheets still leave room for improvementabout flexibility, and are difficult to provide the products to somefields that really need for the elastic property. Overall in the past, apractically usable film or sheet was unobtainable, which can exhibitsufficient mechanical properties such as strength or flexibility or thelike as well as satisfactory heat resistance simultaneously.

The fabrics that possess moisture permeability and water proofingproperty simultaneously can release steam due to sweat of bodies fromthe fabrics yet prevent penetration of rain into the fabrics. In orderto add such functions, coating or lamination of polyamino acid urethaneresins, polyurethane resins, or polytetrafluoroethylene resins on afabric is well-known.

A fabric coated with ordinary polyurethane resins has shown a defect ofsteamy feeling in wearing fabrics due to its inferior moisturepermeability. In order to solve the problem, proposed is a method ofapplying a mixture of polyurethane resins and hygroscopic charcoalpowders on a fabric. (Japanese Japanese Patent Publication for Laid-Open13277/1997.) A fabric laminated with micro-porous film ofpolytetrafluoroethylene shows excellent moisture permeability andwaterproofing property. But the micro-pore is easily stuffed up withdusts leading to the inferior moisture permeability. The producedfabrics feel hard, thus are not suited for practical use, especially forfabrics, but the applications are not limited.

Molded products of plastic resins have long been employed in a widefield of medical treatment, hygiene, or pharmaceuticals. They have beenused largely as they are light-weight and free from damages comparedwith metals and glass, can be molded into various shapes such as film ortube, and can be applied to disposable application due to their ratherinexpensive costs. Concerning their physical characteristics, durabilityat sterilization treatment such as steam sterilization under highpressures, radiation sterilization, or sterilization using ethyleneoxide is required. The easiness of treating waste is also required. Inaddition, the transparency of the base material is needed in some uses.

Polyethylene plastic resins have generally excellent impact resistance,flexibility, and transparency, but do not endure high pressure steamsterilization individually at not less than 110° C. owing to their lowmelting points. For the reason, it becomes necessary to lower thetemperature of sterilization and to prolong the sterilization timeaccordingly. High-density modification of the resin improves the heatresistance, but, on the other hand, sacrifices transparency orflexibility instead.

Polypropylene resins exhibit higher softening points and heat resistancecompared with polyethylene resins. But they often lack enoughflexibility and impact strength especially at low temperatures, whenused alone, for soft bags, films, or tubes due to their rather highmodulus of elasticity. Therefore, they are generally employed as blendswith other soft resins or elastomer resins, or multi-laminated moldedproducts.

EVA (Ethylene-Vinyl Acetate) copolymers have excellent transparency andflexibility, but show inferior heat resistance. Besides they frequentlycause bleed-out of the acetate component by heating or sterilization. Inorder to obtain heat resistance, it is necessary to add a process ofcross-linking using radiation of electron beam.

In order to solve these problems, Japanese Patent Publication forLaid-Open 337164/1993 and Japanese Patent Publication for Laid-Open317411/1993 disclose medical materials using various cyclic polyolefinresins such as norbornene resins or cross-linked cyclic polyolefinresins. With regard to PVC resins, they generate dioxins, which has abad influence on the environment at disposal, thus there is a hesitationto use it.

DISCLOSURE OF INVENTION

The present invention has been devised in view of the above-listedproblems. Its first object is to provide thermoplastic elastomers thathave excellent moisture permeability and light resistance, and toprovide a production method thereof. The second object is to providethermoplastic elastomers that have a high block property for their hardsegment components and soft segment components, and that have excellentflexibility and mechanical strength, especially excellent propertiessuch as settling resistance at high temperatures, and moisturepermeability, processing ability for painting solution, or lightresistance and to provide a production method thereof.

Thus the present invention has its object of providing fibers made fromthermoplastic elastomers with excellent moisture permeability andmoisture-releasing property, and fabrics made from said fibers.

In view of the above problems in the existent technique, the presentinvention also aims at providing films or sheets that have excellentmoisture permeability, waterproofing property, and flexibility.

In view of the above problems in the existent techniques, moreparticularly, the present invention aims at providing fabric withexcellent moisture permeability, waterproofing property, and dressingfeeling and further aims at provision of fabrics, tents, and shoes withcomfortable feeling that are made from such materials.

The present invention aims at providing molded products for medicaltreatment made from thermoplastic elastomers that have excellentflexibility, heat resistance, sterilization resistance, and facileprocessing ability for steam sterilization. Particularly the presentinvention aims at providing containers such as infusion bags; tubes usedfor infusion set, blood transfusion system, or catheter; and injectionmolded parts such as stoppers thereof.

Note that the moisture permeability in the present invention is definedas a phenomenon in which the moisture is absorbed into one side of anobject, and released from the other side of the object.

Namely the Present Invention Relates to:

(1) A thermoplastic elastomer, which comprises a polyether component (A)as a constituting unit, wherein the carbon/oxygen atomic ratio for thepolyoxyalkylene group (—C_(n)H_(2n)O—) constituting the above polyethercomponent is in the range from 2.0 to 2.5, the content of the polyethercomponent in the thermoplastic elastomer is in the range from 50 to 95weight %, and the glass transition temperature of the thermoplasticelastomer is not more than −20° C.

(2) A thermoplastic elastomer as described in (1), wherein the polyethercomponent (A) is bonded with a poly-isocyanate component (C).

(3) A thermoplastic elastomer as described in (1) or (2), wherein thenumber-average molecular weight of the polyether component (A) is in therange from 500 to 5,000.

(4) A thermoplastic elastomer as described in any one of (1) to (3),wherein the polyether component (A) comprises a polyethylene glycolcomponent.

(5) A thermoplastic elastomer as described in any one of (1) to (4),wherein a polyester component (B) is contained as a constituting unitand the number-average molecular weight of said polyester component isin the range from 500 to 10,000.

(6) A thermoplastic elastomer as described in any one of (1) to (5),wherein a polyester component (B) is contained as a constituting unit,and said polyester component (B) comprises 50 to 100 weight % of ashort-chain polyester component represented by the following generalformula (1) and 50 to 0 weight % of a long-chain polyester componentrepresented by the following general formula (2).—CO—R₁—CO—O—R₂—O—  (1)

-   -   (wherein R₁ denotes (i) a divalent aromatic hydrocarbon group of        6 to 12 carbons and/or (ii) a divalent alkylene group of 2 to 10        carbons or a divalent cycloaliphatic hydrocarbon of 6 to 12        carbons. R₂ denotes an alkylene group of 2 to 8 carbons and/or a        divalent cycloaliphatic radical of 6 to 12 carbons).        —CO—R₃—CO—O—R₄—  (2)    -   (wherein R₃ denotes (i) a divalent aromatic hydrocarbon group of        6 to 12 carbons and/or (ii) a divalent alkylene group of 2 to 10        carbons, or a divalent cycloaliphatic hydrocarbon group of 6 to        12 carbons. R₄ comprises a repeating unit of —R₅—O—, and R₅ is        an alkylene group of 2 to 8 carbons).

(7) A thermoplastic elastomer as described in any one of (5) or (6),wherein the polyester component (B) comprises a dicarboxylic acidcomponent of which the molar ratio of the aromatic dicarboxylic acidgroup to the aliphatic dicarboxylic acid group is in the range from100:0 to 40:60.

(8) A thermoplastic elastomer as described in any one of (5) to (7),wherein the polyester component (B) comprises a diol component of whichthe molar ratio of the linear aliphatic diol group to the cycloaliphaticdiol group is in the range from 100:0 to 40:60.

(9) A thermoplastic elastomer as described in any one of (5) to (8),wherein the polyester component (B) comprises polybutylene terephthalatein 40 to 90 weight %.

(10) A thermoplastic elastomer as described in any one of (2) to (9),wherein the poly-isocyanate component (C) comprises (i) an aliphaticpoly-isocyanate component, (ii) a cycloaliphatic poly-isocyanatecomponent, or (iii) a poly-isocyanate component in which the isocyanategroup is not directly bonded to the aromatic ring.

(11) A thermoplastic elastomer as described in any one of (2) to (10),wherein the poly-isocyanate component (C) comprises a diisocyanatecomponent represented by the following general formula (3).—O—CO—NH—R₆—NH—CO—O—  (3)

-   -   (wherein R₆ denotes an alkylene group of 2 to 15 carbons, a        divalent cycloaliphatic hydrocarbon group, a phenylene group, a        methylene group, or a composite radical of alkylene group and        phenylene group).

(12) A thermoplastic elastomer containing a polyether component (A) as aconstituting unit, which is characterized by that

-   1) the water absorption ratio of the thermoplastic elastomer is in    the range from 50 to 200 weight %,-   2) the storge modulus of elasticity of the thermoplastic elastomer    at 40° C. is in the range from 1×10⁶ Pa to 25×10⁶ Pa, and-   3) the glass transition temperature of the thermoplastic elastomer    is not more than −20° C.

(13) A thermoplastic elastomer as described in 12, wherein thethermoplastic elastomer comprising a polyether component (A) as aconstituting unit is the thermoplastic elastomer defined in any one of(1) to (11).

(14) A production method of thermoplastic elastomer as described in anyone of (2) to (13), which comprises the first process of producing aprepolymer by reacting a polyether compound (a) with a poly-isocyanatecompound (c), and the second process of reacting the prepolymer with apolyester compound (b).

(15) A fiber comprising a thermoplastic elastomer as described in anyone of the (1) to (13).

(16) A fabric comprising a fiber as described in (15).

(17) An elastomer film or sheet comprising a thermoplastic elastomer asdescribed in any one of (1) to (13).

(18) An elastomer film or sheet produced by a method comprising thefirst process of manufacturing a prepolymer by reacting a polyethercompound (a) and a poly-isocyanate compound (c) and the second processof reacting the prepolymer with a polyester compound (b) and moldingcontinuously the reaction product or the second step.

(19) A moisture permeable waterproofing fabric, which is produced bylaminating a fabric on at least one side of an elastomer film or sheetas described in (17) or (18).

(20) A fabric, wherein at least one side of the fabric is coated with acomposition containing the thermoplastic elastomer as described in anyone of (1) to (13).

(21) A moisture permeable waterproofing fabric as described in (19) or(20), wherein said fabric comprises an elastomer fiber.

(22) An elastomer film, sheet, or a moisture permeable waterproofingfabric as described in any one of (17) to (21), wherein the moisturepermeability of the elastomer film, sheet or said moisture permeablewaterproofing fabric is not less than 2,000 g/m²(24 hr).

(23) Fabrics, tents, or shoes comprising a moisture permeablewaterproofing fabric as described in any one of (20) to (22).

(24) A molded product for medical use obtained by molding thethermoplastic elastomer as described in any one of (1) to (11).

The thermoplastic elastomer according to the present invention containsa polyether component (A) as a constituting unit. The carbon/oxygenatomic ratio for the polyoxyalkylene chain (—C_(n)H_(2n)O—) thatconstitutes the polyether component (A) is preferably in the range from2.0 to 2.5. When the carbon/oxygen atomic ratio is larger than 2.5, theaffinity with the obtained elastomer and water is decreased, and themoisture permeability or the moisture absorption is diminished. At thesame time, the ratio is larger than 2.5, the function of steamsterilization for the molded object of said elastomer used for medicaluse is degraded.

Concerning the polyether component (A), polyethylene glycol having saidcarbon/oxygen atomic ratio of 2.0 is preferred. It may be a mixture ofpolyether having said ratio of not less than 3.0 and polyethyleneglycol, in which the total carbon/oxygen atomic ratio can be adjusted tobe not more than 2.5.

With regard to the polyether component having said carbon/oxygen atomicratio of not less than 3.0, there can be mentioned, for example,polypropylene glycol (poly-1,3-propylene glycol or poly-1,2-propyleneglycol, for example), poly-tetramethylene glycol, poly-hexamethyleneglycol, poly-(ethylene glycol-tetramethylene glycol) copolymer,poly-(ethylene glycol-propylene glycol) copolymer, and others.

The number-average molecular weight for the polyether component (A) ispreferably in the range from 500 to 5,000, more preferably in the rangefrom 500 to 3,000. With the number-average molecular weight less than500, the flexibility of the obtained elastomer may be decreased,occasionally accompanied by diminished moisture permeability or moisturereleasing property. On the other hand, with the number-average molecularweight exceeding 5,000, the compatibility with the other components suchas the polyester component (B) is decreased, which induces smallerpolymerization degree of the obtained elastomer, and occasionallyresults in the insufficient mechanical strength of the product. Thenumber-average molecular weight is more preferably in the range from1,000 to 2,000.

Note that the number-average molecular weight of the polyether component(A) corresponds to the average molecular weight of the followingpolyether (a).

The content of polyether component (A) in the thermoplastic elastomeraccording to the present invention is usually from 40 to 95 weight %,preferably from 50 to 95 weight %. When the content of polyethercomponent (A) is below 50 weight %, the storage modulus of elasticity iselevated (the elasticity is decreased) together with the loweredmolecular mobility, moisture permeability or moisture releasingproperty. On the other hand, when the polyether component (A) is morethan 95 weight % on the other hand, the product does not exhibit enoughmechanical strength. The content of the polyether component (A) ispreferably from 55 to 90 weight %, more preferably from 60 to 90 weight%.

The glass transition temperature of the thermoplastic elastomeraccording to the present invention is usually not more than −20° C. Whenthe glass transition temperature is higher than −20° C., the elastomerdoes not exhibit sufficient rubber elasticity at low temperatures. Inaddition, molecular mobility is lowered, leading to the deterioratedmoisture permeability or moisture releasing property. The glasstransition temperature is preferably not more than −30° C.

The glass transition temperature of the present invention is defined asthe temperature at which the maximum tangent loss (tanδ) obtained byviscoelasticity measurement on the micro Brownian motion of themolecules of the thermoplastic elastomer appears. This glass transitiontemperature can be measured by a viscoelasticity spectrometer (forexample, RSA-II of Rheometric Scientific Ltd.)

The thermoplastic elastomer according to the present inventionpreferably contains a polyester component (B) as a constituting unit.Preferably the polyester component comprises 50 to 100 weight % of ashort-chain polyester component represented by the following generalformula (1) and 50 to 0 weight % of a long-chain polyester componentrepresented by the general formula (2). With the short-chain componentless than 50 weight %, the melting point of the polyester component (B)is lowered, occasionally giving a bad influence on the mechanicalstrength of the obtained elastomer at high temperatures.—CO—R₁—CO—O—R₂—O—  (1)

-   -   (wherein R₁ denotes (i) a divalent aromatic hydrocarbon group of        6 to 12 carbons and/or (ii) a divalent alkylene or        cycloaliphatic hydrocarbon group of 2 to 10 carbons, and R₂        denotes an alkylene group of 2 to 8 carbons and/or a divalent        cycloaliphatic hydrocarbon group of 6 to 12 carbons.)        —CO—R₃—CO—O—R₄—  (2)    -   (wherein R₃ denotes (i) a divalent aromatic hydrocarbon group of        6 to 12 carbons and/or (ii) a divalent alkylene or        cycloaliphatic hydrocarbon group of 2 to 10 carbons, and R₄ is        constituted from a repeating unit of —R₅—O—, wherein R₅ denotes        an alkylene group of 2 to 8 carbons.)

The above short-chain polyester component may be obtained by reacting anaromatic dicarboxylic acid or its ester and/or an aliphatic dicarboxylicacid or its ester with a low molecular diol. The long-chain polyestercomponent may be obtained by reacting an aromatic dicarboxylic acid orits ester and/or an aliphatic dicarboxylic acid or its ester with a highmolecular diol.

Examples of the aromatic dicarboxylic acid and its ester include, forexample, terephthalic acid, iso-phthalic acid, ortho-phthalic acid,naphthalene-dicarboxylic acid, para-phenylene dicarboxylic acid,dimethyl terephthalate, dimethyl iso-phthalate, dimethyl orthophthalate,dimethyl naphthalene-dicarboxylate, and dimethyl para-phenylenedicarboxylate, and so on. They may be employed singly or in a mixed formof more than two kinds.

Examples of aliphatic dicarboxylic acid or its ester include, forexample, succinic acid, adipic acid, suberic acid, sebacic acid,1,2-cyclohexane dicarboxylic acid, 1,4-cyclohexane dicarboxylic acid,dimethyl succinate, dimethyl adipate, dimethyl suberate, dimethylsebacate, dimethyl 1,2-cyclohexane dicarboxylate, dimethyl1,4-cyclohexane dicarboxylate, and so on. They may be employed singly orin a mixed form of more than two kinds.

The mole ratio of aromatic dicarboxylic acid to aliphatic dicarboxylicacid, two of which constitute the polyester component (B), is preferablyfrom 100:0 to 40:60. When the mole ratio of aliphatic dicarboxylic acidis not less than 60, the melting point of the produced polyestercomponent (B) is lowered, frequently giving a bad influence on themechanical strength of the obtained elastomer at high temperatures.

Concerning the low molecular diol, there are linear aliphatic diol andcycloaliphatic diol, etc. Examples of linear aliphatic diol include, forexample, ethylene glycol, 1,2-propane diol, 1,3-propane diol, 1,3-butanediol, 1,4-butane diol, neopentyl glycol, 1,5-pentane diol, 1,6-hexanediol, diethylene glycol, triethylene glycol, and so on. They may beemployed singly or in a mixed form of more than two kinds. Examples ofcycloaliphatic diol include, for example, 1,4-cyclohexane dimethanol1,2-cyclohexane diol, 1,4-cyclohexane diol and so on. They may beemployed singly or in a mixed form of more than two kinds.

In the above general formula (2), R₅ denotes, for example, an alkylenegroup of 2 to 8 carbons. The component consisted of the repeating unitrepresented by —R₅—O— includes the same diols containing the abovealkylene group (R₂). Examples of R₄ include, for example, polyethyleneglycol, poly-(1,3-propylene glycol), poly-(1,2-propylene glycol),poly-tetramethylene glycol, poly-hexamethylene glycol, poly-(ethyleneglycol-tetramethylene glycol) copolymer, poly-(ethylene glycol-propyleneglycol) copolymer. They may be employed singly or in a mixed form ofmore than two kinds.

In the above general formula (2), R₄ denotes a component constitutedfrom a repeating unit represented by —R₅—O—. Its number-averagemolecular weight is preferably from 500 to 5,000. When thenumber-average molecular weight is less than 500, the block property ofthe polyester component (B) is diminished, leading to the loweredmelting point of the obtained elastomer, thus resulting in inferiormechanical strength of the elastomer at high temperatures. When thenumber-average molecular weight is larger than 5,000, the compatibilitywith the polyether component is diminished, leading to smallerpolymerization degree of the obtained elastomer, and resulting in theinsufficient mechanical strength of the production of fibers. Thenumber-average molecular weight is more preferably in the range from 500to 2,000.

The mole ratio of linear aliphatic diol to cycloaliphatic diol, both ofwhich constitute the polyester component (B), is preferably in the rangefrom 100:0 to 40:60. With the ratio of the aliphatic diol larger than60, the melting point of the produced polyester component (B) iselevated, occasionally giving a bad influence on the solubility of theobtained elastomer into solvents. The mole ratio is more preferably inthe range from 90:10 to 40:60.

The polyester component (B) preferably contains 40 to 90 weight % ofpolybutylene terephthalate. When the amount of polybutyleneterephthalate is less than 40 weight %, the melting point of thepolyester component (B) is lowered, occasionally giving influence on themechanical strength of the obtained elastomer at high temperatures. Onthe other hand, when the polybutylene terephthalate is more than 90weight %, the crystallinity of the elastomer is enhanced, thusoccasionally giving a bad influence on the solubility of the obtainedelastomer into solvents. The content of polybutylene terephthalate inthe polyester component (B) is more preferably from 40 to 80 weight %,and more preferably from 50 to 75 weight %.

There are no limitations about the solvent for dissolving the elastomer.Preferred examples include, for example, polar solvents such asN,N-dimethyl formamide (DMF), N-methyl pyrrolidone (NMP), N,N-dimethylacetoamide, methylethyl ketone (MEK), dioxane, toluene, and so on.

Examples of the high molecular diol include polyethylene glycol,polypropylene glycol, polytetramethylene glycol, poly-hexamethyleneglycol, poly(ethylene glycol-tetramethylene glycol) copolymer, ethyleneoxide-tetrahydrofuran copolymer, poly (ethylene glycol-propylene glycol)copolymer, and so on.

The number-average molecular weight of above-mentioned polyestercomponent is preferably in the range from 500 to 10,000, more preferablyin the range from 500 to 5,000. When the number-average molecular weightless than 500, the block property of the obtained elastomer isdecreased, occasionally leading to the lowered melting point, andresulting in the inferior mechanical strength of the obtained elastomerat high temperatures. When the number-average molecular weight is largerthan 10,000, on the other hand, the compatibility with the polyethercomponent (A) is decreased, which induces smaller polymerization degreeof the obtained elastomer, occasionally resulting in the insufficientmechanical strength of the product. The number-average molecular weightis most preferably in the range from 500 to 2,000. Note that thenumber-average molecular weight of the polyester component (B)corresponds to average molecular weight of the ordinary polyester (b).

Number-average molecular weight measurements in the present inventionwere carried out under the following conditions.

-   -   Apparatus: HLC 8020 series produced by TOSOH Co.    -   Column: Shodex HFIP 806M (in two).    -   Solvent: hexafluoro-isopropanol        -   (added of 0.005N sodium trifluoro-acetate).    -   Standard: Polymethyl methacrylate (for standard)    -   Temperature: 23° C.

The thermoplastic elastomer according to the present inventioncontaining the polyether component (A) as a constituting unit may beobtained by the known methods. For example, the above aromaticdicarboxylic acid or its ester and/or aliphatic dicarboxylic acid or itsester is treated for the ester-interchange reaction with an excessamount of the above low-molecular diol and, if necessary, abovehigh-molecular diol under the presence of catalysts such as tetrabutyltitanate with heating at 160 to 200° C. This is followed by, forexample, the condensation reaction under reduced pressure at 240 to 250°C. to yield the thermoplastic elastomer.

The thermoplastic elastomer according to the present invention ispreferably contains the thermoplastic elastomer wherein the abovepolyether component (A) is bonded with the poly-isocyanate component(C), or the thermoplastic elastomer wherein the polyether component (A)and the polyester component (B) are connected via the polyisocyanatecomponent (C).

The thermoplastic elastomer according to the present inventionpreferably contains a urethane-bonding component represented by thegeneral formula (3) as the polyisocyanate component (C).—O—CO—NH—R₆—NH—CO—O—  (3)

-   -   (wherein R₆ denotes an alkylene group, a phenylene group, or a        methylene group, or a combined group of alkylene group and        phenylene group.)

Preferred for the thermoplastic elastomer containing theurethane-binding component represented by the general formula (3) can beobtained by condensation of isocyanate compounds with compoundscontaining hydroxyl group at the molecular terminal. Examples includethermoplastic polyurethane elastomer, polyether-ester elastomerelongated of its chain length with isocyanates, polyether-amideelastomer elongated of its chain length with isocyanates, or esterelastomer made by the reaction of a polyester compound (b) and apolyether compound (a) connected via a polyisocyanate compound (c).

To sum up, the preferred examples for the thermoplastic elastomerconstituting the present invention include a block copolymer of thepolyether component (A) and the polyester component (B) in repeatedform. The polyester component (B) comprises 50 to 100 weight % of theshort-chain polyester component represented by the general formula (1),and 50 to 0 weight % of the long-chain polyester component representedby the general formula (2). Here the polyether component (A) and thepolyester component (B) are connected via the poly-isocyanate component(C) represented by the general formula (3) yielding the thermoplasticelastomer compositions.

In order to obtain such thermoplastic elastomer connected via thepoly-isocyanate component (c), the polyether compound (a) and thepolyester compound (b) may be reacted with the poly-isocyanate compound(c).

The molecular structure of poly-isocyanate compound (c) is not limitedspecifically, but it has more than two isocyanate groups within a singlemolecule. When the isocyanate has an isocyanate group directly bonded toan aromatic ring, the product is yellowed under radiation of light, andit will be difficult to use it for the field needing for lightresistance. Thus aliphatic isocyanates, cycloaliphatic isocyanate, ororisocyanates, in which an aromatic ring is not directly connected withthe isocyanate group, are more preferable.

The average content of the isocyanate group per one molecule of thepoly-isocyanate compound (c) is preferably in the range from 2.0 to 2.2.Examples of isocyanate compounds containing two isocyanate groups inaverage include, for example, aromatic diisocyantes such as4,4′-diphenylmethane diisocyanate, tolylene diisocyanate, phenylenediisocyanate, naphthalene diisocyanate, and the like; aliphaticdiisocyanates such as methylene diisocyanate, 1,2-ethylene diisocyanate,1,3-propylene diisocyanate, 1,4-buthane diisocyanate, 1,5-pentamethylenediisocyanate, 1,6-hexamethylene diisocyanate, octamethylenediisocyanate, lysine diisocyanate, and so on; cycloaliphaticdiisocyanate such as 1,4-cyclohexane diisocyanate, 1,3-cyclohexanediisocyanate, isophorone diisocyanate, trimethyl-hexamethylenediisocyanate, hydrogenated 4,4′-phenyl-methane diisocyanate,hydrogenated xylene diisocyanate, and the like; and diisocyanatecompounds in which the isocyanate group is not directly bonded to anaromatic ring such as xylene diisocyanate and tetramethyl-xylenediisocyanate, and so on. The isocyanate wherein the average isocyanategroup in one molecule is in the range from 2.0 to 2.2 can be used bymixting isocyanate compounds that contain average isocyanate groups ofmore than 2.2 and another compounds that contain average isocyanategroups of 2.0 may be allowed.

A typical example of isocyanate compounds that contain averageisocyanate groups of more than 2.2 in one molecule is polymeric MDI. Itscommercial products include ‘Millionate MR200’ (produced by NipponPolyurethane Co.) which contains average isocyanates of 2.8. Otherexamples are triphenyl-methane triisocyanate (average isocyanate of3.0), tris-(isocyanate-phenyl) thiophosphate (average isocyanate of3.0), hexamethylene triisocyanate (average isocyanate of 3.0), lysineester triisocyanate (average isocyanate of 3.0),1,8-diisocyanate-4-isocyanate methyl-octane (average isocyanate of 3.0),and 1,6,11-undecane triisocyanate (average isocyanate of 3.0).

In the present invention, the mole ratio of the isocyanate groupcontained in the poly-isocyanate compound (c) is preferably in the rangefrom 0.60 to 1.05 times to the mole of active hydrogen-containing group(which can react with the above-mentioned isocyanate group) contained inthe polyether compound (a) and the polyester compound (b).

When the mole ratio is smaller than 0.60, the molecular weight of theobtained elastomer is lowered, leading to the insufficient mechanicalstrength. When the mole ratio is larger than 1.05, on the other hand,the obtained elastomer may yield side reaction products such as unstableallophanate group or buret group, which may cause considerabledeterioration in the molding function or the physical properties of theobtained elastomer with a lase of time. The mole ratio is morepreferably in the range from 0.80 to 1.01. Within the ratio, theallophanate group or the buret group hardly generates, and the molecularweight of the obtained elastomer becomes high, leading to its excellentphysical properties.

The thermoplastic elastomer according to the present inventioncomprising the polyether component (A) and the polyester component (B)connected via the polyisocyanate component (C) is preferably producedthrough the first process of manufacturing a prepolymer isocyanated atits both molecular terminals, which is made by reacting the abovepolyether compound (a) and the polyisocyanate compound (c), and thesecond process of reacting the prepolymer with the polyester compound(b) having two hydroxyl groups at its both molecular terminals.

The above polyester compound (b) and the polyether compound (a) haveusually two hydroxyl groups at their molecular terminals, but may alsocontain the carboxyl group within 5 equivalent percent. The prepolymeris polymerized using the connecting component containing theurethane-bonding represented by the general formula (3) when the twoterminal functional groups, which react with the above isocyanatecompound, are both the hydroxyl group. When one molecular terminal ofthe polyester compound (b) or the polyether compound (a) is hydroxylgroup and the other molecular terminal is carboxyl group, the prepolymeris polymerized using the connecting component containing the urethanebonding represented by the general formula (4). When the two molecularterminal functional groups of polyester copolymer are both carboxylgroups, the urethane-bonding can include the parts which can beconnected with the diisocyanate compound represented by the generalformula (5).—O—CO—NH—R₆—NH—CO—  (4)

-   -   (wherein R₆ has the same meaning defined above)        —CO—NH—R₆—NH—CO—  (5)    -   (wherein R₆ has the same meaning defined above) (R₆ is similar        to the note for equation (3).)

The above polyester compound (b) preferably contains hydroxyl group atthe molecular terminals in more than 95 equivalent percent. Hydroxylgroup and carboxyl group are the possible terminal functional group forthe polyester compound (b). When the hydroxyl group is less than 95equivalent percent, the reactivity with the poly-isocyanate compound (c)is diminished, and the polymerization degree of the obtained elastomeris lowered, frequently leading to the insufficient mechanical strengthof the elastomer.

The terminal functional group of the polyester compound (b) can bequantitatively evaluated by using the acid value and the hydroxyl value.The acid value and the hydroxyl value can also be measured by followingmethods, but it is also possible to employ the certified value of themanufacturer.

Acid value: A sample is dissolved into a mixed solvent ofbenzylalcohol/chloroform followed by the neutralization titration usingphenol red as the indicator to obtain the acid value.

Hydroxyl value: A sample is dissolved in a mixed solvent ofnitrobenzene/pyridine with succinic anhydride for reaction for 10 hours,and the reaction solution is mixed with methanol for precipitation. Theobtained reaction product is treated to above-mentioned acid valuemeasurement, and the result is specified as the hydroxyl value.

In the first process described above, the mole ratio of the isocyanategroup contained in the poly-isocyanate compound (c) is preferably in therange from 1.1 to 2.2 times, more preferably in the range from 1.2 to2.0 times to the active hydrogen-containing group, which can be reactedwith the isocyanate group, contained in the polyether compound (a). Whenthe mole ratio is less than 1.1 times, the both molecular terminals ofthe yielding prepolymer can not be converted fully into the isocyanategroup, frequently hindering the reaction in the second process. When theratio is larger than 2.2, on the other hand, the unreacted isocyanatecompound (c) remains in the reaction mixture, which occurs sidereactions yielding sideproducts such as allophanate group or buretgroup. As a result, the molding ability or the physical properties ofthe obtained elastomer are occasionally degraded.

In the above first process, the reaction temperature is preferably inthe range from 100 to 240° C. When the reaction temperature is below100° C., the reaction does not proceed sufficiently. On the other hand,when the temperature is above 240° C., the polyether compound mayfrequently decompose. The reaction temperature is more preferably in therange from 160 to 220° C.

In the second process, the prepolymer formed in the first process isreacted with the above polyester compound (b). The mole ratio of theisocyanate group contained in the above poly-isocyanate compound (c) ispreferably in the range from 0.60 to 1.05 times, more preferably in therange from 0.80 to 1.01 times to the sum of the activehydrogen-containing group contained in the above polyether compound (a)and the active hydrogen-containing group contained in the polyesterpolymer (b). With this limitation, proceeding of side reactions may beprevented, and the molecular weight of the obtained elastomer is largeenough to give excellent physical characters.

In the second process the reaction temperature is preferably in therange from 100 to 240° C. With the reaction temperature below 100° C.,the reaction may not proceed sufficiently. With the reaction temperatureabove 240° C., on the other hand, the prepolymer may frequentlydecompose, thus elastomer with sufficient mechanical strength may not beobtained. The reaction temperature is more preferably in the range from160 to 220° C. In this process, the polyester compound (b) may be melteddown by heating in a different vessel and added to the prepolymer usinga pump, or the polyester compound (b) may be heated with an extruder formeltdown and then added to the prepolymer.

The above reaction is preferably carried out in the bulk state. Withthis reaction method, the reactivity of the second process is improvedsignificantly. With regard to the reaction apparatus, mono-axial orbi-axial extruder can be usually employed, but it is not limitedspecifically. A bi-axial extruder wherein two axes rotate in the samedirection and a bi-axial extruder wherein two axes ratate individuallyin different direction is preferably used due to the excellentefficiency in the stirring and mixing. A bi-axial extruder wherein twoaxes rotate in the same direction is more preferably employed. With thisapparatus, the reactivity of the second process is improvedsignificantly. A tandem extruder is preferably employed for carrying outthe first process and the second process continuously.

It may be possible to use catalysts in the above process of stirring andmixing. Examples of such catalysts include diacyl tin (I), tetraacyl tin(II), dibutyl tin oxide, dibutyl tin laurate, dimethyl tin malate, tindioctanoate, tin tetraacetate, triethylene amine, diethylene amine,triethyl amine, metal salts of naphthenic acid, metal salts of octanoicacid, triisobutyl aluminum, tetrabutyl titanate, calcium acetate,germanium dioxide, and antimony trioxide. They may be used incombination of more than two kinds.

When the prepolymer, wherein two molecular terminals are converted intoisocyanate group which is obtained by reacting the polyether compound(a) with the poly-isocyanate compound (c), is reacted with the polyestercompound (b) containing hydroxyl group at its both molecular terminals,a thermoplastic elastomer comprising block copolymer is obtained stably,in which the polyether component (A) and the polyester component (B) areconnected via the poly-isocyanate component (C). In this case, the chainof polyether compound (a) and the polyester compound (b) may not beprolonged with the poly-isocyanate compound (c) individually. When theprepolymer reacts with the polyester compound (b) partly, the productcan work as a compatibility agent for the polyether compound (a) and thepolyester compound (b). In this case the elastomer production may becomepossible even when the compatibility of the polyether compound (a) andthe polyester compound (b) is insufficient.

It is also possible to convert the molecular terminals of the obtainedthermoplastic elastomer into polyester group by controlling theequivalence for the polyether compound (a), the polyester compound (b),and the isocyanate compound (c), for example, reacting the prepolymerwith an excess amount of the polyester compound (b) in the secondprocess. With this conversion, higher melting points of thethermoplastic elastomer can be accomplished, and the molding property isimproved as well as the physical properties at high temperatures.

It is possible to add stabilizers to the thermoplastic elastomeraccording to the present invention at or after the time of production.Examples of stabilizers are, for example, hindered phenol antioxidantssuch as 1,3,5-trimethyl-2,4,6-tris(3,5,-di-t-butyl-4-hydroxybenzyl)benzene, and 3,9-bis{2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)-propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5,5] undecane; thermalstabilizers such as tris(2,4-di-t-butylphenyl) phosphite, trilaurylphosphite,2-t-butyl-alpha-(3-t-butyl-4-hydroxyphenyl)-p-cumenyl-bis(p-nonylphenyl)phosphite, dimiristyl-3,3′-thiodipropionate,distearyl-3,3′-thiodipropionate, pentaerythrityltetraxis(3-lauryl-thiopropionate), and ditrodecyl-3,3′-thiodipropionate.

It is also possible to add additives including bubble core formingagents, fibers, inorganic fillers, flame retardants, ultravioletsabsorbers, anti-static agents, inorganic substances, and salts of higherfatty acids to the thermoplastic elastomer according to the presentinvention as long as the practical quality of the elastomer is notimpaired.

Examples of the above bubble core forming agents are calcium carbonate,talc, clay, magnesium oxide, zinc oxide, carbon black, silicon dioxide,titanium oxide, sodium hydrogencarbonate, citric acid, ortho-boric acid,and alkaline earth metal salts of fatty acids, of which particle size ispreferably not more than 500 micrometers.

Examples of the above fibers include, for example, glass fibers, carbonfibers, boron fibers, silicon carbonized fibers, alumina fibers,amorphous fibers, inorganic fibers such as silicon fibers/titaniumfibers/ or carbon fibers, and organic fibers such as aramid fibers.

Examples of the above inorganic fillers are, for example, calciumcarbonate, titanium oxide, mica, talc, and so on. Examples of the aboveflame retardants are hexabromo-cyclododecane, tris(2,3-dichloropropyl)phosphate, pentabromo-phenyl-allyl ether, and so on.

Examples of the above ultraviolet absorbers include, for example,p-t-butylphenyl salicylate, 2-hydroxy-4-methoxybenzophenone,2-hydroxy-4-methoxy-2′-carboxybenzophenone,2,4,5-trihydroxy-butylophenone, and so on.

Examples of the above anti-static agents are, for example,N,N-bis(hydroxyethyl)-alkyl amine, alkylaryl sulfonates, alkylsulfonates, and so on.

Examples of the above inorganic substances include barium sulfate,alumina, and silica. Examples of the above salts of higher fatty acidsare sodium stearate, barium stearate, and sodium palmitate, and so on.

The thermoplastic elastomer according to the present invention may bemodified of its properties by blending other thermoplastic resins, orrubber components. Examples of such thermoplastic resins are polyolefin,modified polyolefin, polystyrene, polyvinyl chloride, polyamides,polycarbonates, polysulfones, polyesters, and so on.

Examples of such rubber components include, for example, natural rubber,styrene-butadiene copolymers, polybutadiene, polyisoprene,acrylonitrile-butadiene copolymers, ethylene-propylene copolymers (EPM,EPDM), polychroloprene, butyl rubber, acryl rubber, silicon rubber,urethane rubber, olefin thermoplastic elastomers, styrene thermoplasticelastomers, PVC thermoplastic elastomers, ester thermoplasticelastomers, amide thermoplastic elastomers, and so on.

The thermoplastic elastomer according to the present invention may bemolded into molded products using methods such as press molding,extrusion molding, injection molding, or blow molding. The moldingtemperature varies depending on the melting point of the employedelastomer and the molding method, but is preferably in the range from160 to 250° C. When the molding temperature is lower than 160° C., theflowability of the ester elastomers becomes low, leading to thenon-homogeneous molded products. When the molding temperature is higherthan 250° C., on the other hand, the obtained elastomer decomposesfrequently, yielding products with insufficient mechanical strength.

The thermoplastic elastomer according to the present invention may bepreferably employed for molded parts such as automobile, electric andelectronic parts, industrial parts, sport goods, medical goods, sanitarygoods, and the like.

Examples of the above automobile parts include boots such as equal-speedjoint boots, rack and pinion boots; ball joint seals; safety belt parts;bumper facias; emblems; and molls. Examples of the above electric andelectronic parts are, for example, cable covering materials, gears,rubber switches, membrane switches, tact switches, and O-rings. Examplesof the above industrial parts include, for example, oil pressure hoses,coil tubes, sealing agents, packings, V-belts, rolls, anti-vibrationmaterials, shock absorbers, couplings, and diaphragms.

Examples of the above sport goods are sole of a shoe, balls for ballgames, moisture permeable waterproofing clothes, and so on.

Examples of the above medical goods are containers such as infusion bagsand blood transfusion bags; tubes including infusion set tubes, bloodtransfusion system tubes, and catheters; or the stoppers thereof.

Examples of the above sanitary goods are dehumidication agents, aromaticagents, diapers, menstrual goods, and soon. In addition, thethermoplastic elastomer can be favorably employed for the raw materialof elastomer fibers, elastomer sheets, composite sheets, hot-meltadhesives, and polymer-alloys with other plastic resins.

The fiber according to the present invention is one made from the abovethermoplastic elastomer. The fiber according to the present inventionmay be a composite fiber of the above thermoplastic elastomer and otherfibers, but preferably contains the thermoplastic elastomer in not lessthan 10 weight %. When the content is less than 10 weight %, the productmay not fully exhibit the moisture absorption and moisture-releasingproperty deriving from the thermoplastic elastomer.

The fiber according to the present invention may be produced by spinningthe above thermoplastic elastomer according to the ordinary method. Inmore detail, the thermoplastic elastomer obtained thus above may beprocessed into fibers depending on the known methods such as dryspinning, wet spinning, or melt spinning. The processed form may beeither a staple or a filament.

In order to produce products with thin denier, the melt spinning methodis preferred. To be precise, such thin fibers may be produced either bythe melt spinning of the thermoplastic elastomer after it is oncepelletized, or by spinning the thermoplastic elastomer obtained by themeltdown polymerization, which is directly conveyed to the spinnerest.Taking the spinning stability into account, the method of spinning rightafter polymerization is preferred. The non-drawn fibers obtained by themeltdown and spinning may be heat-treated or drawn in heating.

The fabric according to the present invention is one made from fibers ofthe above thermoplastic elastomer. The fabric according to the presentinvention may be a composite of the fiber of the above thermoplasticelastomer and the fiber of other plastic resins. In the case where afabric is not containing fibers of the thermoplastic elastomer, it willexhibit low absorption s for moisture and sweat. When such fabric isemployed for clothes, it will give the user a sticky feeling due tosweat.

Concerning the molding method of film or sheet, there are various knownmethods including T-die method, inflation method, solution castingmethod (dry coagulation method), or wet coagulation method. The producedfilm or sheet may be drawn or may not be drawn.

The non-drawn film or sheet may be produced, for example, by the meltextrusion on a casting drum.

The mono-axial drawn film or sheet may be produced by interposing anon-drawn elastomer sheet, between two pinch rolls of different rotationrates, drawing said sheet along the lengthwise in heating. In this case,the ratio of rotation rates of the two rolls (the rolling-up roll andthe sending-out roll) corresponds to the elongation percentage.

The bi-axial drawn film or sheet may be obtained by stretching anon-drawn sheet to bi-axial direction simultaneously or consecutively.In the case of consecutive drawing, the order of stretching may be thefirst lengthwise drawing and then widthwise, or vice verse. It is alsopossible to repeat lengthwise and widthwise drawing in more than twotimes for both the simultaneous bi-axial drawing or the consecutivebi-axial drawing.

The elongation percentage of the film or the sheet to the lengthwise orthe widthwise direction may be freely determined depending on thetargeted drawing degree, strength, or the modulus of elasticity of thedesired film or sheet, but it is preferably in the range from 2.5 to5.0. The elongation percentage, it can be set to be the same values ordifferent values for the lengthwise direction and the widthwisedirection respectively. It is also possible to carry out a heatingprocess for the film or sheet after the bi-axial drawing. It may becarried out in any of the known methods such as in an oven or on aheated roll.

It may be carried out loosening the film or sheet to the lengthwise orthe widthwise direction.

The elastomer film or sheet according to the present invention may beproduced by molding pellets of the above thermoplastic elastomer usingknown methods. But it is preferable to mold the molten thermoplasticelastomer continuously through dice directly after the above two-steppedmanufacture of the thermoplastic elastomer due to the following reasons.

One reason is the preparation procedure for the molding becomes verycomplicated. Since the thermoplastic elastomer consisting elastomer filmor sheet according to the present invention readily absorbs moisture, itis quite important to carry out the moisture management of pellet inorder to produce molded products of uniform quality, with a method ofmolding after pelletizing.

The second reason is the coagulation of pellets. When the soft segmentof the elastomer is increased for improving the flexibility and moisturepermeability of the produced elastomer film or sheet, this phenomenon isapt to arise and degrades the handling property at the molding process.

The layer of the thermoplastic elastomer according to the presentinvention may be mono-layer or multi-layer.

In the multi-layer, polyamide resins or polyester resins may preferablybe used for the lamination.

The laminated film or sheet according to the present invention isproduced by laminating at least one fabric on one surface of the aboveelastomer film or sheet, but the kinds or laminating methods are notlimited specifically.

The fabric used in the present invention includes, for example,non-woven fabric, woven or knitted fabric. The above non-woven fabric isnot limited to these examples in any manner, for example, non-wovenfabric made by dry methods including needle punch method, spun lacemethod, spun bond method, or melt blow method; non-woven fabric made bywet methods such as paper making method; non-woven fabric by thecombination of wet method and dry method; and laminates of thesenon-woven fabric.

Examples of fibers constituting the above non-woven fabric are, thoughnot limited in any manner, natural fibers such as cotton, hemp, wool,and the like; cellulose regenerated fibers; synthetic fibers onpolyamide, polyester, polyolefin, polystyrene, polyacryl, polyvinylalcohol or the like; and inorganic fibers made of pulp or glass fiber.These fibers may be employed singly or in mixed form. Among themsynthetic fibers on polyolefin, polyester, and polyamide are favorablyemployed due to their durability.

Examples of the above woven or knitted fabric include, though notlimited to the examples in any manner, woven fabrics of basic wave suchas plain weave, twill weave, or sateen weave; derivative weave;combination weave; and knits of warp knitting, weft knitting, orcircular knitting.

Examples of fibers constituting the above woven or knitted fabric are,though not limited to these examples in any manner, synthetic fibers onpolyamide, polyester, polyacrylonitrile, or polyvinyl alcohol;semi-synthetic fibers such as triacetate; or mix-spun fibers includingnylon-6/cotton or polyethylene terephthalate/cotton.

Preferably these fabrics should have the elasticity, though not limitedin any manner. The advantages of the elasticity are, for example, in thecase of making clothes, it is superior in fitting sense and easy tomove.

The coating method of fabric with the thermoplastic elastomer accordingto the present invention is not limited in any manner, but the adhesivelaminating method, in which the elastomer film or sheet is adhered to afabric using adhesives, or the heat-melt laminating method utilizingheat may be listed as examples. In particular, preferably employed isthe extrusion laminating method, in which the elastomer film or sheet isextrusion-molded in heating, quickly laminated with a fabric while itretains the heat-melt quality, and pressed with a roll for stableadhesion.

The moisture permeable waterproofing fabric according to the presentinvention may be produced as previously described.

The moisture permeability is determined on the Japanese JIS Z 0208.

The moisture permeability of the moisture permeable waterproofing fabricis not less than 2,000 g/m²(24 hr), preferably not less than 4,000g/m²(24 hr), more preferably not less than 6,000 g/m²(24 hr).

With the above moisture permeability of less than 2,000 g/m²(24 hr), anadequate air permeability is not obtainable. When such fabric is usedfor clothes, it readily provokes dew condensation, gives wet or stickyfeeling to a wearer, and results in the uncomfortable sense for thewearer.

The thickness of the moisture permeable waterproofing fabric ispreferably from 0.05 to 5 mm, more preferably from 0.05 to 3 mm, andmore preferably from 0.1 to 2 mm. The thinner fabrics are apt to break,and the thicker fabrics lose their moisture permeability.

The molded product used for medical treatment according to the presentinvention may be manufactured by known methods such as press molding,extrusion molding (tube molding, inflation molding, T-die molding,etc.), injection molding, blow molding, vacuum molding, compressionmolding, calendar molding, or solution casting. The preferred moldingtemperature varies depending on the melting point and the molding methodof the thermoplastic elastomer that is used for medical treatment, butpreferably is below 250° C. With the molding temperature above 250° C.,the thermoplastic elastomer becomes to decompose, yielding elastomerwith insufficient mechanical strength. The injection-molded products formedical treatment according to the present invention may take the formof film, sheet, tube, bag, or stoppers thereof.

The present invention provides a thermoplastic elastomer comprising apolyether component (A) as a constituting unit, which is characterizedby the following factors:

-   -   1) The water absorption ratio of the thermoplastic elastomer is        in the range from 50 to 200 weight %,    -   2) The storage modulus of elasticity of the thermoplastic        elastomer at 40° C. ranges from 1×10⁶ Pa to 25×10⁶ Pa,    -   3) The glass transition temperature of the thermoplastic        elastomer is less than −20° C.

The water absorption ratio is preferably in the range from 50 to 200weight %. It is largely affected by the content of the polyethercomponent in the thermoplastic elastomer and by the affinity of thepolyether with water. With the water absorption ratio of less than 50weight %, the obtained affinity of elastomer with water decreases,leading to the inferior moisture permeability. With the water absorptionratio of more than 200 weight %, the elastomer exhibits considerablydegraded physical properties when it is absorbing water, which may beunacceptable for the practical use. The water absorption ratio is morepreferably in the range from 60 to 150 weight %.

The water absorption ratio of the thermoplastic elastomer may bedetermined by the following procedure:

(1) A test piece (sheet of 50 mm×50 mm×1 mm) is dried thoroughly in adesiccator containing silica gel, and measured of its weight (W₀).

(2) It is impregnated in ion-exchanged water at 23° C. for 24 hours, andmeasured of its weight (W₁).

(3) The water absorption ratio=(W₁−W₀)×100/W₀ (weight %).

It is also preferable that the storage modulus of elasticity of thethermoplastic elastomer at 40° C. is in the range from 1×10⁶ Pa to25×10⁶ Pa. The storage elastic modulus is largely influenced by thecontent of the polyether component in the thermoplastic elastomer. Whenthe storage elastic modulus is less than 1×10⁶ Pa, the mechanicalstrength of the elastomer becomes insufficient. When the storage elasticmodulus is larger than 25×10⁶ Pa, the molecular mobility of theelastomer is suppressed, leading to the degraded moisture permeability.The storage elastic modulus of the thermoplastic elastomer is preferablyin the range from 5×10⁶ Pa to 15×10⁶ Pa.

The thermoplastic elastomer according to the present invention may beeasily manufactured by the above methods or selecting the thermoplasticelastomer satisfying the above condition 1), 2) and 3) from thethermoplastic elastomer produced by the above methods.

The thermoplastic elastomer according to the present invention isimproved of its affinity with water by comprising the soft segment madefrom specific polyether component, which accelerates the absorption ofwater molecule. Further, the molecular mobility of the elastomer hasbeen activated by employing the specific glass transition point and thespecific content of the soft segment, which also accelerate thediffusion of water molecule. With these molecular designs, the elastomerbecomes a material having extraordinary high moisture permeability.

It also becomes an elastomer material of excellent light resistance byemploying the aliphatic and the cycloaliphatic isocyanate group, or theisocyanate-containing aromatic compound, in which the isocyanate groupis not directly bonded to the aromatic ring.

The thermoplastic elastomer according to the present invention exhibitsits elastomeric characters due to the formation of cross-linkingconnections at its crystalline component, which is mainly made from theshort-chain polyester component. In more detail, the thermoplasticelastomer comprises a short-chain polyester-rich component having a highblock property and a polyether-rich component, and contains a morereadily crystallizing short-chain polyester component compared with theexisting polyester thermoplastic elastomers with similar elasticity. Asa result, stronger cross-linking points are formed, yielding thethermoplastic elastomer materials that possess excellent flexibility andmechanical characters at high temperatures simultaneously.

The water absorption or moisture absorption of the fiber is controlledby the adsorption of water molecules at the surface of the fiber. Andthe water releasing property is controlled by the diffusion of watermolecules within the fiber and evaporation of water molecules from thesurface, which has the lower partial pressure of water vapor.

The thermoplastic elastomer according to the present invention exhibitshigher affinity with water due to its specific composition of the softsegment, which promotes the absorption of water. The molecular mobilityof the elastomer is further promoted by having the specific glasstransition temperature and the specific content of the soft segment,which also accelerate the diffusion of water molecules. on thesemolecular designs, the fibers made from the thermoplastic elastomeraccording to the present invention and fabric made of these fibers haveaccomplished the extraordinary high water absorption and moisturerelease.

The elastomer film or sheet according to the present invention exhibitshigh affinity with water due to its soft segment comprising a specificpolyether component, which promotes the adsorption of water.Furthermore, the molecular mobility of elastomer has been promoted byhaving the specific glass transition temperature and the specificcontent of the soft segment, which also accelerate the diffusion ofwater molecules. on these molecular designs, the elastomer materialsaccording to the present invention are equipped with the extraordinaryhigh water moisture permeability.

The thermoplastic elastomer constituting elastomer film or sheetaccording to the present invention exhibits its elastomeric charactersdue to the formation of cross-linking connections at its crystallinesegment, which comprises a short-chain polyester component. In moredetail, the thermoplastic elastomer comprises a short-chainpolyester-rich component having a high block property and apolyether-rich component, and contains a more readily crystallizingshort-chain polyester component compared with the existing polyesterthermoplastic elastomers with similar elasticity. As a result, strongercross-linking points are formed, yielding the thermoplastic elastomermaterials possessing excellent flexibility and mechanical characters athigh temperatures simultaneously.

The thermoplastic elastomer composition according to the presentinvention used for production of moisture permeable waterproofing fabricexhibits higher polarity of the resin layer, higher affinity with water,and resultantly higher moisture permeability by setting itscarbon/oxygen atomic ratio for the polyether component to be 2.0 to 2.5.When the polyether component of the thermoplastic elastomer was set inthe range from 50 to 95 weight %, and its glass transition temperatureis controlled at less than −20° C., the product exhibits improveddiffusion of water vapor in the resin and accordingly higher moisturepermeability.

The moisture permeable waterproofing fabric according to the presentinvention is equipped with high moisture permeability and waterproofingproperty due to lamination of the above thermoplastic elastomercomposition, and is suitable for clothes, tents, or shoes.

The molded product for medical treatment according to the presentinvention comprises the thermoplastic elastomer possessing the followingfeatures, and possesses an extraordinary high steam sterilizationpropaty. The constituting thermoplastic elastomer exhibits higheraffinity with water due to the soft segment comprising a specificpolyether component, and accelerates the adsorption of water molecules.Furthermore, the molecular mobility has been promoted with the specificglass transition temperature and the specific content of the softsegment, which also accelerate the diffusion of water molecules. onthese molecular designs, the elastomer materials according to thepresent invention are equipped with the extraordinary high moisturepermeability.

The thermoplastic elastomer according to the present invention exhibitsits elastomeric characters due to the formation of cross-linkingconnections at its crystalline segment, which comprises a short-chainpolyester component. In more detail, the thermoplastic elastomercomprises a short-chain polyester-rich component having a high blockproperty and a polyether-rich component, and contains a more readilycrystallizing short-chain polyester component compared with the existingpolyester thermoplastic elastomers with similar elasticity. As a result,stronger cross-linking points are formed, yielding elastomer materialspossessing excellent flexibility and mechanical characters at hightemperatures simultaneously. Thus, the molded product for medicaltreatment is superior in elasticity, heat resistance and sterilizationresistance.

Thermoplastic elastomer according to the present invention exhibitshigher affinity with water due to its specific water absorption ratio,which accelerates the adsorption of water molecules. Furthermore, themolecular mobility has been promoted with the specific glass transitiontemperature and the specific sotred modulus of elasticity, which alsoaccelerate the diffusion of water molecules. On these molecular designs,the elastomer materials according to the present invention are equippedwith the extraordinary high moisture permeability.

The thermoplastic elastomer according to the present invention exhibitsits elastomeric characters due to the formation of cross-linkingconnections at its crystalline segment, which comprises a short-chainpolyester component. In more detail, the thermoplastic elastomercomprises a short-chain polyester-rich component having a high blockproperty and a polyether-rich component, and contains a more readilycrystallizing short-chain polyester component compared with the existingpolyester thermoplastic elastomers with similar elasticity. As a result,stronger cross-linking points are formed, yielding the thermoplasticelastomer materials possessing excellent flexibility and mechanicalcharacters at high temperatures simultaneously.

Among the objects and problems to be solved in the present invention,the provision of elastomer with excellent flexibility, mechanicalcharacteristics at high temperatures, and especially settling resistanceat high temperatures, and the provision of the production method thereofare solved by the part I of the present invention mentioned above. Theobjects and problems may also be solved by the following part II of thepresent invention.

The detailed description of the preferred embodiments for the part I ofthe present invention is given in the reference examples 1 to 6, theexamples 1 to 31, the comparative examples 1 to 16, and the tables 1 to7. The detailed description of the preferred embodiments for the part IIof the present invention is given in the examples 32 to 35, thecomparative examples 21 and 22, and the tables 11 and 12.

In the present patent specification, therefore, the following sectiondown to the preferred embodiments of the present invention belongs tothe part II of the present invention.

In view of the above description, the part II according to the presentinvention relates to an ester elastomer that has a high block propertyfor the hard segment components and soft segment components, hascompatibility of elasticity and mechanical strength at hightemperatures, especially settling resistance at high temperatures, aproduction method thereof, an amide elastomer, and a production methodthereof. And it also provides a production method of amide-elastomer andamide-elastomer.

The problems and the objects for the part II of the present inventionmay be solved by the following means.

(1) A production method of ester elastomer wherein a polyester component(S) and a polymeric component (T) possessing hydroxyl group at the twomolecular terminals are combined via an isocyanate component (U) to forman ester block copolymer, in which the isocyanate component is expressedby the general formula (51),—O—CO—NH—R¹′—NH—CO—O—  (51)

-   -   (wherein R¹′ denotes an alkylene group of 2 to 15 carbons,        —C₆H₄— (phenylene group), —C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—) or by        the general formula (52),        —O—CO—NH—R²′—NH—CO—  (52)    -   (wherein R²′ denotes an alkylene group of 2 to 15 carbons,        —C₆H₄— (phenylene group), —C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—); the        polyester component (S) comprises a repeating unit expressed by        the general formula (53),        —CO—R³′—CO—O—R⁴′—O—  (53)    -   (wherein R³′ denotes a divalent aromatic hydrocarbon group of 6        to 12 carbons, and R⁴′ denotes an alkylene group of 2 to 8        carbons); the polymeric component (T) possessing hydroxyl group        at the two molecular terminals has the glass transition        temperature of not more than 20° C. and the number-average        molecular weight of in the range from 500 to 5,000; the ester        elastomer comprises 50 to 2,000 parts by weight of the polymeric        component (T) with hydroxyl group at the two molecular terminals        and 10 to 100 parts by weight of the isocyanate component (U)        relative to 100 parts by weight of the polyester component (S),        and the production method of the ester elastomer comprises the        following two processes; i) production of prepolymer by reacting        the polymeric component (T) possessing hydroxyl group at the two        molecular terminals with the diisocyanate compound (U′) and ii)        reaction of the above prepolymer with the polyester component        (S).

(2) A production method of ester elastomer according to the above (1),wherein the polymeric component (T) comprises polyether having arepeating unit expressed by the general formula (54),—R⁵′—O—  (54)

-   -   (wherein R⁵′ denotes an alkylene group of 2 to 10 carbons).

(3) A production method of ester elastomer according to the above (1),wherein the polymeric component (T) comprises aliphatic polyester havinga repeating unit expressed by the general formula (55),—R⁶′—O—CO—R⁷′—CO—O—  (55)

-   -   (wherein R⁶′ and R⁷′ denote, same or differently, alkylene group        of 2 to 10 carbons).

(4) A production method of ester elastomer according to the above (1),wherein the polymeric component (T) comprises polylactone having arepeating unit expressed by the general formula (56),—R⁸′—CO—O—  (56)

-   -   (wherein R⁸′ denotes an alkylene group of 2 to 10 carbons).

(5) A production method of ester elastomer according to the above (1),wherein the polymeric component (T) comprises a polycarbonate having a arepeating unit expressed by the general formula (57),—R⁹′—O—CO—O—  (57)

-   -   (wherein R⁹′ denotes an alkylene group of 2 to 10 carbons).

(6) An ester elastomer produced by the production method for the esterelastomer according to the above (1) through (5).

(7) A production method of amide elastomer, wherein a polyamidecomponent (P) and the polymeric component (T) possessing hydroxyl groupat the two molecular terminals are combined through an isocyanatecomponent (Q) to form an amide block copolymer, in which the isocyanatecomponent is expressed by the general formula (58),—O—CO—NH—R¹⁰′—NH—CO—O—  (58)

-   -   (wherein R¹⁰′ denotes an alkylene group of 2 to 15 carbons,        —C₆H₄— (phenylene group), —C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—), or by        the general formula (59),        —O—CO—NH—R¹¹′—NH—CO—NH—  (59)    -   (wherein R¹¹′ denotes an alkylene group of 2 to 15 carbons,        —C₆H₄— (phenylene group), —C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—), the        polyamide component (P) comprises a repeating unit expressed by        the general formula (60),        —CO—R¹²′—CO—NH—R¹³′—NH—  (60)    -   (wherein R¹²′ and R¹³′ denote, same or differently, alkylene        group of 2 to 12 carbons), or a repeating unit expressed by the        general formula (61),        —CO—R¹⁴′—NH—  (61)    -   (wherein R¹⁴′ denotes an alkylene group of 2 to 12 carbons), the        polymeric component (T) possessing hydroxyl group at the two        molecular terminals has the glass transition temperature is not        more than 20° C. and the number-average molecular weight in the        range from 500 to 5,000; the amide elastomer comprises 50 to        2,000 parts by weight of the polymeric component (T) possessing        hydroxyl group at the two molecular terminals and 10 to 100        parts by weight of the isocyanate component (Q) relative to 100        parts by weight of the polyamide component (P), and the        production method of the amide elastomer comprises the following        two processes; i) production of prepolymer by reacting the        polymeric component (T) possessing hydroxyl group at the two        molecular terminals with a diisocyanate compound (Q′) and ii)        the process of reacting the above prepolymer with the polyamide        component (P).

(8) A production method of amide elastomer according to the above (7)wherein the polymeric component (T) comprises polyether having arepeating unit expressed by the general formula (54),—R⁵′—O—  (54)

-   -   (wherein R⁵′ denotes an alkylene group of 2 to 10 carbons).

(9) A production method of amide elastomer according to the above (7)wherein the polymeric component (T) comprises aliphatic polyester havinga repeating unit expressed by the general formula (55),—R⁶′—O—CO—R⁷′—CO—O—  (55)

-   -   (wherein R⁶′ and R⁷′ denote, same or differently, alkylene group        of 2 to 10 carbons).

(10) A production method of amide elastomer according to the above (7),wherein the polymeric component (T) comprises polylactone having arepeating unit expressed by the general formula (56),—R⁸′—CO—O—  (56)

-   -   (wherein R⁸′ denotes an alkylene group of 2 to 10 carbons).

(11) A production method of amide elastomer according to the above (7),wherein the polymeric component (T) comprises polycarbonate having arepeating unit expressed by the general formula (57),—R⁹′—O—CO—O—  (57)

-   -   (wherein R⁹′ denotes an alkylene group of 2 to 10 carbons).

(12) An amide elastomer produced by the production method for the amideelastomer according to the above (7) through (11). In the presentinvention, the polyester component (S) comprises a repeating unitexpressed by the general formula (53),—CO—R³′—CO—O—R⁴′—O—  (53)

-   -   (wherein R³′ denotes a divalent aromatic hydrocarbon group of 6        to 12 carbons, and R⁴′ denotes an alkylene group of 2 to 8        carbons).

The above polyester component (S) may be obtained by the reaction of anaromatic dicarboxylic acid or its ester derivative with a low-moleculardiol.

The above aromatic dicarboxylic acid or its ester derivative is notlimited in any manner. Examples of them include terephthalic acid,isophthalic acid, orthophthalic acid, naphthalene dicarboxylic acid,paraphenylene dicarboxylic acid, dimethyl terephthalate, dimethylisophthalate, dimethyl orthophthalate, naphthalene dicarboxylic aciddimethyl ester, and paraphenylene dicarboxylic acid dimethyl ester. Theymay be employed singly or in mixed form of more than two kinds. Amongthem naphthalene dicarboxylic acid and naphthalene dicarboxylic aciddimethyl ester are most preferable as the settling resistance at hightemperatures for the ester elastomer according to the present inventionis significantly improved using these compounds.

Examples of the above low-molecular diol include, though not limited tothe examples in any manner, ethylene glycol, 1,2-propanediol,1,3-propanediol, 1,3-butanediol, 1,4-butane diol, neopentyl glycol, 1,5-pentane diol, and 1,6-hexane diol. They may be employed singly or inmixed form of more than two kinds.

Polymerization of the above polyester component (S) may be conducted byusing known methods. For example, dimethyl terephthalate may be heatedwith an excess amount of low-molecular diol at 200° C. in the presenceof catalysts for the ester interchange reaction, followed by thecondensation reaction at 240° C. under a reduced pressure to yield thepolyester component (S).

In the polymerization reaction for obtaining the above polyestercomponent (S), polyols that have hydroxyl group at the two molecularterminals can be used, which improves the compatibility with thepolymeric component (T) that has also hydroxyl group at the twomolecular terminals.

The polyols are not limited in any manner. But they have preferably theglass transition temperature of not more than 20° C. and thenumber-average molecular weight of 500 to 5,000. Examples of suchpolyols are polyethers, aliphatic polyesters, polylactones, orpolycarbonates. Among them most preferably used are polyols that have acomponent similar to the employed polymeric component (T).

The content of polyols that have hydroxyl group at the two molecularterminals in the above polyester component (S) is not limited in anymanner, but is preferably 5 to 50 weight % of the above polyestercomponent (S). When the content is less than 5 weight %, the effect ofimproving the compatibility with the polymeric component (T) isdiminished. When the content is larger than 50 weight %, the meltingpoint of the obtained polyester component (S) is lowered giving a badinfluence on the mechanical strength of the ester elastomer at hightemperatures. The content is most preferably in the range from 10 to 30weight %.

The range of the number-average molecular weight of the above polyestercomponent (S) is not limited in any manner, but preferably is 50 to5,000. When the molecular weight is less than 500, the block property ofthe ester elastomer is decreased giving a bad influence on themechanical strength at high temperatures. When the molecular weight islarger than 5,000, the compatibility with the polymeric component (T) isdiminished, leading to smaller polymerization degrees for the obtainedester elastomer, which results in the elastomer with insufficientmechanical strength. The molecular weight is more preferably in therange from 1,000 to 3,000.

The intrinsic viscosity of the above polyester component is not limitedin any manner, but is preferably 0.05 to 0.5. When the intrinsicviscosity is less than 0.05, the block property of the ester elastomeris decreased, giving a bad influence on the mechanical strength at hightemperatures. When the intrinsic viscosity is larger than 0.5, thecompatibility with the polymeric component (T) is diminished, leading tosmaller polymerization degrees for the obtained ester elastomer, whichresults in the elastomer with insufficient mechanical strength. Theintrinsic viscosity is more preferably in the range from 0.1 to 0.3. Inthe present patent specification, the intrinsic viscosity means a valuemeasured at 25° C., employing ortho-chlorophenol as the solvent.

In the present invention, the polymeric component (T) that has hydroxylgroup at the two molecular terminals is defined to have the glasstransition temperature of less than 20° C. and the number averagemolecular weight in the range from 500 to 5,000. When the glasstransition temperature is higher than 20° C. for the above polymericcomponent (T), the obtained ester elastomer becomes hard, and does notexhibit excellent rubber elasticity. The glass transition temperature ispreferably less than 0° C., more preferably less than −20° C.

When the number-average molecular weight of above polymeric component(T) is less than 500, the obtained ester elastomer loses sufficientflexibility. When the number-average molecular weight is above 5,000,the obtained elastomer loses enough reactivity with the diisocyanatecompound (U′) leading to lower degrees of polymerization andinsufficient mechanical strength of the obtained ester elastomer. Thenumber-average molecular weight is preferably in the range from 500 to3,000, more preferably in the range from 500 to 2,000.

The polymeric component (T) is not limited in any manner as long as theaforementioned conditions are satisfied. The preferred examples includepolyethers, polylactones, aliphatic polyesters, polycarbonates,polyolefins, polybutadiene, polyisoprene, polyacrylates, andpolysiloxanes. Among them, polyethers, polylactones, aliphaticpolyesters, polycarbonates are more preferable due to their excellentreactivity.

The preferred species of polyether for the above polymeric component (T)is not limited in any manner, but preferably it is a polyethercomprising a repeating unit expressed by the following general formula(54),—R⁵′—O—  (54)

-   -   (wherein R⁵′ denotes an alkylene group of 2 to 10 carbons).

The polyether for the above polyether comprising a repeating unitexpressed by the general formula (54) is not limited in any manner.Examples of them include polyethylene glycol, poly-1,3-propylene glycol,poly-1,2-propylene glycol, polytetramethylene glycol, polyhexamethyleneglycol. Among them preferably used is polytetramethylene glycol, as ithas excellent mechanical properties and weather resistance. Examples ofits commercial products are “PTHF” (trade name) produced by BASF and“PTMG” (trade name) produced by Mitsubishi Chemical.

The number-average molecular weight of the above polyether is preferablyin the range from 500 to 5,000. With the number-average molecular weightof less than 500, the obtained ester elastomer loses sufficientflexibility. With the number-average molecular weight above 5,000, theobtained elastomer loses enough reactivity with the diisocyanatecompound (U′), leading to lower degrees of polymerization andinsufficient mechanical strength for the obtained ester elastomer. Thenumber-average molecular weight is more preferably in the range from 500to 3,000 and most preferably in the range from 500 to 2,000.

The aliphatic polyester for the above polymeric component (T) is notlimited in any manner, but preferably it is an aliphatic polyestercomprising a repeating unit expressed by the following general formula(55),—R⁶′—O—CO—R⁷′—CO—O—  (55)

-   -   (wherein R⁶′ and R⁷′ denote, same or differently, alkylene group        of 2 to 10 carbons).

The aliphatic polyester comprising a repeating unit expressed by thefollowing general formula (55) is not limited in any manner, and may beprepared by the polycondensation reaction of aliphatic dicarboxylic acidand aliphatic diol. The above aliphatic dicarboxylic acid is not limitedin any manner. Examples of them include oxalic aid, malonic acid,succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid,azelaic acid, and sebacic acid. It is also possible to add otherdicarboxylic acids as long as the physical property of the moldedproduct obtained by the ester elastomer is not impaired by the addition.They may be employed singly or in mixed form of more than two kinds.

The above aliphatic diol is not limited in any manner. Examples of theminclude ethylene glycol, 1,2-propane diol, 1,3-propane diol, 1,3-butanediol, 1,4-butane diol, neopentyl glycol, 1,5-pentane diol, and1,6-hexane diol. It is also possible to add other diols as long as thephysical property of the molded product obtained by the ester elastomeris not impaired by the addition. They may be employed singly or in mixedform of more than two kinds.

Examples of its commercial product are “Nippolan 4009”, “Nipponlan4010”, and “Nippolan 4070” (all are trade names) produced by NipponPolyurethane Co.

The number-average molecular weight of the above aliphatic polyester ispreferably in the range from 500 to 5,000. When the number-averagemolecular weight is less than 500, the obtained ester elastomer losessufficient flexibility. When the number-average molecular weight isabove 5,000, the obtained elastomer loses enough reactivity with thediisocyanate compound (U′) leading to lower degrees of polymerizationand insufficient mechanical strength for the obtained ester elastomer.The number-average molecular weight is more preferably in the range from500 to 3,000 and most preferably in the range from 500 to 2,000.

The polylactone for the above polymeric component (T) is not limited inany manner, but preferably it is a polylactone comprising a repeatingunit expressed by the following general formula (56),—R⁸′—CO—O—  (56)

-   -   (wherein R⁸′ denotes an alkylene group of 2 to 10 carbons).

The polylactone comprising a repeating unit expressed by the abovegeneral formula (56) is not limited in any manner, and may be preparedby the ring-opening polymerization reaction of lactones.

The above lactone is not limited in any manner. The preferred examplesare lactones of 3 to 10 carbons. Among them caprolactone is particularlypreferable. They may be employed singly or in mixed form of more thantwo kinds. The examples of its commercial product are “TONE Polyol”(trade name) produced by Union Carbide Co, and so on.

The number-average molecular weight of the above polylactone ispreferably in the range from 500 to 5,000. When the number-averagemolecular weight is less than 500, the obtained ester elastomer losessufficient flexibility. When the number-average molecular weight isabove 5,000, the obtained elastomer loses enough reactivity with thediisocyanate compound (U′) leading to lower degrees of polymerizationand insufficient mechanical strength for the obtained ester elastomer.The number-average molecular weight is more preferably in the range from500 to 3,000 and most preferably in the range from 500 to 2,000.

The polycarbonate for the above polymeric component (T) is not limitedin any manner, but preferably it is a polycarbonate comprising arepeating unit expressed by the following general formula (57),—R⁹′—O—CO—O—  (57)

-   -   (wherein R⁹′ denotes an alkylene group of 2–10 carbons).

The polycarbonate comprising a repeating unit expressed by the abovegeneral formula (57) is not limited in any manner, and may be preparedby the ring-opening polymerization reaction of aliphatic carbonates.

The above aliphatic carbonate is not limited in any manner. Thepreferred examples are aliphatic carbonates of 4 to 10 carbons. Amongthem propylene carbonate, tetramethylene carbonate, and hexamethylenecarbonate are preferable. The examples of commercial product for theabove polycarbonate are “Nippolan 981” (trade name) produced by NipponPlyurethance Co, and so on.

The number-average molecular weight of the above polycarbonate ispreferably in the range from 500 to 5,000. When the number-averagemolecular weight is less than 500, the obtained ester elastomer losessufficient flexibility. When the number-average molecular weight isabove 5,000, the obtained elastomer loses enough reactivity with thediisocyanate compound (U′) leading to lower degrees of polymerizationand insufficient mechanical strength for the obtained ester elastomer.The number-average molecular weight is more preferably in the range from500 to 3,000 and most preferably in the range from 500 to 2,000.

The ester elastomer according to the present invention is defined as theblock-copolymer of the above polyester component (S) and the polymericcomponent (T) possessing hydroxyl group at the two molecular terminals,which are connected with the isocyanate component (U).

To obtain the above ester elastomer by reacting the polyester component(S) and the polymeric component (T) with the isocyanate compound (U′)having hydroxyl group at the two molecular terminals, the polyestercomponent (S) and the polymeric component (T) having hydroxyl group atthe two molecular terminals should be reacted with the diisocyanatecompound (U′) expressed by the general formula (62).

Usually the above polyester component (S) and the polymeric component(T) possess hydroxyl group at their two molecular terminals. But theymay be substituted with carboxyl group partly. When the two functionalgroups of the two components reacting with the diisocyanate compound(U′) are both hydroxyl group, the two components may be connected withthe isocyanate component (U) expressed by the following general formula(51). When one functional group is hydroxyl group and the otherfunctional group is carboxyl group, they are connected with theisocyanate component (U) expressed by the general formula (52).

When one functional group is carboxyl group and the other is alsocarboxyl group of polyester component (S) and polymeric component (T),they may contain a fragment connected with the isocyanate component,which is expressed by the following general formula (63),—O—CO—NH—R¹′—NH—CO—O—  (51)—O—CO—NH—R²′—NH—CO—  (52)—OCN—R¹⁵′—NCO—  (62)—CO—NH—R¹⁶′—NH—CO—  (63)

In these formula (51), (52), (62) and (63), R¹′, R²′, R¹⁵′ and R¹⁶′denote an alkylene group of 2 to 15 carbons, —C₆H₄— (phenylene group),—C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—) group. Also, R¹′, R²′, R¹⁵′ and R¹⁶′ maybe a composite functional group of the above groups.

The structure of the above diisocyanate compound (U′) is not limited inany manner as long as it has two isocyanate groups in a single molecule.It is also possible to employ other compounds possessing more than threeisocyanate groups in one molecule as long as the flowability of theobtained ester elastomer is kept within a normal range. They may be usedsingly or in mixed form of more than two kinds.

Examples of the above diisocyanate compound (U′) are aromaticdiisocyanates such as 4,4′-diphenylmethane diisocyanate, tolylenediisocyanate, phenylene diisocyanate, naphthalene diisocyanate, and soon; aliphatic diisocyanates such as 1,2-ethylene diisocyanate,1,3-propylene diisocyanate, 1,4-butane diisocyanate, 1,6-hexamethylenediisocyanate; 1,4-cyclohexane diisocyanate, 1,3-cyclohexanediisocyanate, isophorone diisocyanate, hydrogenated4,4′-di-phenyl-methane diisocyanate, and so on.

The ester elastomer according to the present invention comprises 50 to2,000 parts by weight of the polymeric component (T), and 10 to 100parts by weight of the isocyanate component (U) relative to 100 parts byweight of the polyester component (S).

When the polymeric component (T) is less than 50 parts by weight, theobtained ester elastomer loses sufficient flexibility. When thepolymeric component (T) is more than 2,000 parts by weight, the obtainedester elastomer loses sufficient mechanical strength. The content ispreferably in the range from 200 to 1,000 parts.

When the isocyanate component (U) is less than 10 parts by weight, theobtained ester elastomer does not reach the sufficient molecular weightleading to inferior mechanical strength. With the isocyanate component(U) is more than 100 parts by weight, the obtained ester elastomer losessufficient flexibility. The content is preferably in the range from 30to 70 parts.

The production method of ester elastomer according to the presentinvention comprises the following two-step processes; {circle around(1)} The production process of prepollymer by reacting the polymericcomponent (T) possessing hydroxyl group at the two molecular terminalswith the diisocyanate compound (U′) {circle around (2)} The process ofreacting above prepolymer with the polyester component (S). Theadvantages Features of the above production method according to thepresent invention are as follows;

(1) Usually different polymeric components are not mutually compatible,so it is difficult to react with each other. When the polymericcomponent (T) and the polyester component (S) are reacted simultaneouslywith the diisocyanate compound (U′), the simultaneous reaction of thethree components does not yield block copolymer, but yield a blendedmixture of polyester and polymer. Instead, the polymeric component (T)or the polyester component (S) extends predominantly with thediisocyanate compound (U′). According to the present invention, however,the terminal isocyanate group in the prepolymer comprising the polymericcomponent (T) can be reacted securely with the polyester component (S),yielding the block copolymer. In order to enhance the reactivity in thiscase, the reaction apparatus and the reaction temperature are thecritical factors.

(2) In the next process, an excess molar amount of the polyestercomponent (S) is reacted with prepolymer. This effects yield blockcopolymers, of which the molecular terminal is sealed with the hardsegment, that is the polyester component.

The physical property of the product thus obtained as an elastomervaries to a large extent depending on the terminal kinds of the blockcopolymer. When the terminal is the soft segment of the polymericcomponent (T), this segment does not only contribute to the expressionof rubber elasticity, but also lowers the melting point of thecrystalline hard segment, inducing inferior creep resistance andmechanical strength at high temperatures. When the terminal is the hardsegment, on the other hand, it will improve the creep resistance andmechanical strength at high temperatures. The production method ofthermoplastic elastomer according to the present invention isspecifically suited for obtaining block copolymers, of which themolecular terminal is sealed with the hard segment that is expected toimprove the creep resistance and mechanical strength at hightemperatures.

The illustrative embodiments of the production method according to thepresent invention are described hereinafter in detail.

In the above first process, it is preferable to react the polymericcomponent (T) with an excess amount of the diisocyanate compound (U′).The molar ratio of the diisocyanate compound (U′) to the polymericcomponent (T) is most preferably in the range from 1.1 to 2.2 times.With the ratio less than 1.1 times, the two molecular terminals of theobtained prepolymer are not completely converted to isocyanate group,which may inhibit the reaction in the second process. With the ratioexceeding 2.2 times, a part of the diisocyanate compound (U′) is leftunreacted after the reaction, which may cause side reactions in thesecond process. The molar ratio is more preferably in the range from 1.2to 2.0 times.

The reaction temperature in the above first process is preferably in therange from to 100 to 240° C. With the temperature below 100° C., thereaction may not proceed sufficiently. With the temperature exceeding240° C., the polymeric component (T) starts to decompose. The reactiontemperature is more preferably in the range from 120 to 160° C.

In the above second process, the obtained prepolymer is reacted with thepolyester component (S) with a molar ratio of 0.9 to 3.0 times. In orderto obtain block copolymers, of which the molecular terminals are sealedwith the hard segment of polyester, the prepolymer may be reactedpreferably with an excess molar amount of the polyester component (S).Particularly, the molar ratio of the polyester component (S) to theprepolymer is preferably in the range from 1.2 to 3.0 times. With themolar ratio less than 1.2 times, the reaction may partly yield blockcopolymers having the soft segment in the molecular terminal. With themolar ratio exceeding 3.0, the flexibility of the obtained esterelastomer becomes inferior. The molar ratio is more preferably in therange from 1.25 to 2.0 times.

It is possible to control the structure of the obtained block copolymersby changing the composition ratio of the polyester component (S) and thepolymeric component (T). If the hard segment is referred to as A and thesoft segment is referred to as B, block copolymers of ABA type areobtained when the molar ratio of the polyester component (S) to theprepolymer is 2.0 times. When the molar ratio of the polyester component(S) to the prepolymer is 1.5 times, block copolymers of ABABA type areobtained. When the molar ratio of the polyester component (S) to theprepolymer is 1.25 times, furthermore, block copolymers of ABABABABAtype are obtained.

The ester elastomer having significantly improved creep resistance andmechanical strength at high temperatures may be prepared by reacting ablock copolymer, of which the two molecular terminals are sealed withthe hard segment of the polyester component, with the diisocyanatecompound (U′). Then it is followed by further molecular weighttreatment. This yields a block copolymer having excellent creepresistance and mechanical strength at high temperatures.

If the molecular terminals of the hard segment are not the requisite, itis preferable, for obtaining the ester elastomer of high molecularweight, to react the prepolymer with the polyester component (S) at amolar ratio of 0.9 to 1.2 times. With the molar ratio off the range, itbecomes difficult to raise the molecular weight.

In the case where the two molecular terminals of the prepolymer employedin the second process are not completely converted to isocyanate group,the ester elastomer with high molecular weight may be obtained by thefollowing method. The polyester component (S) is first reacted with anexcess molar amount of diisocyanate compound (U′), yielding anotherpolyester compound (S) having isocyanate group at the two molecularterminals. Then this product is further reacted with the aboveprepolymer to give the ester elastomer with high molecular weight. Inthe above series of reactions, the molar amount of diisocyanate compound(U′) is preferably in the range from 0.9 to 1.2 times to the sum of thepolymeric component (T) and the polyester component (S). With the molarratio off the range, it becomes difficult to raise the molecular weight.

In the above second process, the reaction temperature is preferably inthe range from 180 to 260° C. With the temperature below 180° C., thepolyester component does not completely melt-down. As a result thereaction does not proceed smoothly, leading to decreased molecularweight for the obtained product. With the temperature exceeding 260° C.,the prepolymer and the diisocyanate compound (U′) starts to decompose,giving polymers with insufficient mechanical strength. The reactiontemperature is more preferably in the range from 200 to 240° C.

It is possible to employ catalysts for the above reaction in theproduction method according to the present invention. Examples of theabove catalysts are diacyl tin (II), tetraacyl tin (IV), dibutyl tinoxide, dibutyl tin dilaurate, dimethyl tin malate, tin dioctanoate, tintetraacetate, triethylene amine, diethylene amine, triethyl amine, metalsalts of naphthenic acid, metal salts of octanoic acid, triisobutylaluminum, tetrabutyl titanate, calcium acetate, germanium dioxide,antimony trioxide and so on. They may be used singly or in combinationof more than two kinds.

The above reaction is preferably carried out in bulk. With this reactionmethod, the reactivity of the second process may be significantlyimproved. With regard to the reaction apparatus, an extruder may beemployed.

As above extruder, a bi-axial extruder wherein two axes rotate in thesame direction is preferable. With this extruder, the reactivity,especially the reactivity of the second step can be improved. A tandemextruder is preferably employed for carrying out the first process andthe second process continuously.

It is possible to use stabilizers in the production method according tothe present invention. It is also possible to add stabilizers to theester elastomer produced by the production method of the ester elastomeraccording to the present invention. Examples of the stabilizers includehindered phenol antioxidants such as1,3,5-trimethyl-2,4,6-tris(3,5,-di-t-butyl-4-hydroxybenzyl) benzene,3,9-bis{2-[3-(3-t-butyl-4-hydroxy-5-methylphenyl)-propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5,5] undecane, and thelike; thermal stabilizers such as tris(2,4-di-t-butylphenyl) phosphate,trilauryl phosphite,2-t-butyl-alpha-(3-t-butyl-4-hydroxyphenyl)-p-cumenyl-bis(p-nonylphenyl)phosphite, dimiristyl-3,3′-thiodipropionate,distearyl-3,3′-thiodipropionate, pentaerystyryl tetraxis(3-lauryl-thiopropionate), ditridecyl-3,3′-thiodipropionate, and so on.They may be used singly or in mixed form of more than two kinds.

The part II of the present invention relates to an ester elastomerproduced by the production method according to the part I of the presentinvention.

The ester elastomer according to the part II of the present invention isproduced by the production method according to the part I of the presentinvention. It exhibits high block property for the hard segmentcomponent and the soft segment component as well as the excellentflexibility and the mechanical characteristics at high temperatures,including especially the settling property at high temperatures.

During or after the production, it is also possible to add additivesincluding fibers, inorganic fillers, flame retardants, UV lightabsorbers, anti-static agents, inorganic substances, and salts of higherfatty acids to the ester elastomer according to the part II of thepresent invention as long as the practicality of the elastomer is notimpaired. They may be used singly or in mixed form of more than twokinds.

Examples of the above fibers are not limited to the examplesspecifically, but include inorganic fibers such as glass fibers, carbonfibers, boron fibers, silicon carbide fibers, alumina fibers, amorphousfibers, inorganic fibers made of silicon, titanium, or carbon, andorganic fibers such as Aramid. Examples of the above inorganic fillersare, though not limited to the examples, calcium carbonate, titaniumoxide, mica, and talc.

Examples of the above flame retardants are, though not limited to theexamples, but include hexabromo-cyclododecane, tris(2,3-dichloropropyl)phosphate, pentabromo-phenyl-allyl ether, and so on.

Examples of the above UV light absorbers are, though not limited to theexamples, but include p-t-butylphenyl salicylate,2-hydroxy-4-methoxybenzophenone,2-hydroxy-4-methoxy-2′-carboxybenzophenone,2,4,5-trihydroxy-butylophenone, and so on.

Examples of the above anti-static agents are, though not limited to theexamples, but include N,N-bis (hydroxyethyl)-alkyl amine, alkylarylsulfonates, alkyl sulfonates, and so on.

Examples of the above inorganic substances are, though not limited tothe examples, but include barium sulfate, alumina, silicon oxide, and soon.

Examples of the above salts of higher fatty acids are, though notlimited to the examples, but include sodium stearate, barium stearate,sodium palmitate, and so on.

The ester elastomer according to the part II of the present inventionmay be modified of its properties by blending other thermoplasticresins, rubber components, or the like. Examples of such thermoplasticresins are, though not limited to the examples, but include polyolefin,modified polyolefin, polystyrene, polyvinyl chloride, polyamide,polycarbonate, polysulfone, and polyester.

Examples of such rubber components are, though not limited to theexamples, but include natural rubber, styrene-butadiene copolymers,polybutadiene, polyisoprene, acrylonitrile-butadiene copolymers,ethylene-propylene copolymers (EPM, EPDM), polychroloprene, butylrubber, acryl rubber, silicon rubber, urethane rubber, olefinthermoplastic elastomers, styrene thermoplastic elastomers, PVCthermoplastic elastomers, ester thermoplastic elastomers, amidethermoplastic elastomers, and so on.

The ester elastomer according to the part II of the present inventionmay be shaped to molded products using conventional methods such aspress molding, extrusion molding, injection molding, or blow molding.The molding temperature varies depending on the melting point of theemployed elastomer as well as the molding method, but preferably it isin the range from 160 to 280° C. With the molding temperature lower than160° C., the flowability of the ester elastomers becomes inferior,leading to non-homogeneous molded products. With the molding temperaturehigher than 280° C., on the other hand, the obtained elastomer starts todecompose, yielding products with insufficient mechanical strength.

The molded products made from ester elastomer according to the part IIof the present invention may be favorably employed for molded parts ofautomobile, electric and electronic parts, industrial parts, sportgoods, medical goods, and so on.

Examples of the above automobile parts are not limited specifically, butinclude boots such as equal-speed joint boots, rack and pinion boots;ball joint seals; safety belt parts; bumper facias; emblems; and molls.

Examples of the above electric and electronic parts are, though notlimited to the examples, but include cable-covering materials, gears,rubber switches, membrane switches, tact switches, and O-rings.

Examples of the above industrial parts are, though not limited to theexamples, but include oil pressure hoses, coil tubes, sealing parts,packings, V-belts, rolls, anti-vibration materials, shock absorbers,couplings, diaphrams, and binders for bonded magnets.

Examples of the sport goods are, though not limited to the examples, butinclude sole of shoe and balls for ball games. Examples of the abovemedical goods are, though not limited to the examples, but includecontainers such as infusion bags and blood transfusion bags; tubesincluding infusion set tubes, blood transfusion system tubes, andcatheters; and the stoppers themselves.

In addition, the thermoplastic elastomer according to the part II of thepresent invention may be favorably employed for the raw material ofelastomer fibers, elastomer sheets, composite sheets, films, compositefilms, form, hot-melt adhesives, binders, polymer-alloys together withother plastic resins, and so on.

The thermoplastic elastomer according to the part II of the presentinvention has excellent elasticity and physical properties at hightemperatures owing to the following reasons. Usually different polymericcomponents are not mutually compatible, and difficult to react with eachother. But the polymeric component (T) belonging to the soft segmentcomponent and the polyester component (S) belonging to the hard segmentcomponent can bond with each other by controlling the reaction with thediisocyanate compound (Q′). As a result, an ester elastomer of very highblock property concerning the hard segment component and the softsegment component may be produced. The ester elastomer exhibits itscharacter as an elastomer by forming cross-linked points in thecrystalline polyester component.

Since the ester elastomer according to the part II of the presentinvention comprises the polyester-rich segment and soft-rich segment,the polyester component is to crystallize more easily than ordinaryester elastomers having a similar elasticity. As a result, rigidcross-linking points are formed, producing elastomer materials havingsuperior mechanical characteristics at high temperatures. The presenceof a section of soft-rich segment increases the average molecular weightbetween cross-linking points. This leads to elastomer materials havingsuperior elasticity.

The part III of the present invention relates to a production method ofamide elastomer. It yields amide elastomers, in which the blockcopolymers comprising the above polyamide component (P) and thepolymeric component (T) possessing hydroxyl group at the two molecularterminals are connected through the isocyanate component (Q) expressedby the general formula (58),—O—CO—NH—R¹⁰′—NH—CO—O—  (58)

-   -   (wherein R¹⁰′ denotes an alkylene group of 2 to 15 carbons,        —C₆H₄— (phenylene group), —C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—) or by        the general formula (59),        —O—CO—NH—R¹¹′—NH—CO—NH—  (59)    -   (wherein R¹¹′ denotes an alkylene group of 2 to 15 carbons,        —C₆H₄— (phenylene group), —C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—); the        polyamide component (P) comprises a repeating unit expressed by        the general formula (60),        —CO—R¹²′—CO—NH—R¹³′—NH—  (60)    -   (wherein R¹²′ and R¹³′ denote, same or differently, alkylene        group of 2 to 12 carbons), or a repeating unit expressed by the        general formula (61),        —CO—R¹⁴′—NH—  (61)    -   (wherein R¹⁴′ denotes an alkylene group of 2 to 12 carbons); the        polymeric component (T) possessing hydroxyl group at the two        molecular terminals has the glass transition temperature of not        more than 20° C. and the number-average molecular weight in the        range from 500 to 5,000; and the amide elastomer comprises 50 to        2,000 parts by weight of the polymeric component (T) possessing        hydroxyl group at the two molecular terminals and 10 to 100        parts by weight of the isocyanate component (Q) relative to 100        parts by weight of the polyamide component (P). The amide        elastomer may be produced in the following two processes;        {circle around (1)} Production of prepolymer by reacting the        polymeric component (T) possessing hydroxyl group at the two        molecular terminals with the diisocyanate compound (Q′), and        {circle around (2)} Process of reacting the above prepolymer        with the polyamide component (P).

In the part III of the present invention, the polyamide component (P)comprises a repeating unit expressed by the general formula (60),—CO—R¹²′—CO—NH—R¹³′—NH—  (60)

-   -   (wherein R¹²′ and R¹³′ denote, same or differently, alkylene        group of 2 to 12 carbons), or a repeating unit expressed by the        general formula (61),        —CO—R¹⁴′—NH—  (61)    -   (wherein R¹⁴′ denotes an alkylene group of 2 to 12 carbons).

The above polyamide component (P) may be obtained by thepolycondensation of diamine with dicarboxylic acid, or by thering-opening polymerization of lactam.

Examples of the above diamine are, though not limited to the examples,but include ethylenediamine, tetramethylenediamine,hexamethylenediamine, octamethylenediamine, decamethylenediamine,dodecamethylenediamine, and the like. They may be employed singly or inmixed form of more than two kinds.

Examples of the above dicarboxylic acid are, though not limited to theexamples, but include oxalic acid, malonic acid, succinic acid, glutaricacid, adipic acid, pimelic acid, suberic acid, azelaic acid, and sebacicacid. It is also possible to add other dicarboxylic acids as long as thephysical property of the molded product by the obtained amide elastomeris not impaired by the addition. They may be employed singly or in mixedform of more than kinds.

Examples of the above lactam are, though not limited to the examples,but include valerolactam, caprolactam, dodecalactam, and soon. They maybe employed singly or in mixed form of more than two kinds.

It is possible to polymerize the above polyamide component (P) by knownmethods. For example, hexamethylenediamine is heated with an equimolaramount of dicarboxylic acid at 260° C. in the presence of catalysts forthe polycondensation reaction, yielding the polyamide component (P). Orε-caprolactam is heated at 260° C. in the presence of catalysts for thering-opening polymerization to yield the polyamide component (P).

Examples of the polyamide component (P) obtained by the above methodsare, though not limited to the examples, but include 4-nylon, 6-nylon,6,6-nylon, 11-nylon, 12-nylon, 6,10-nylon, 6,12-nylon and so on.

In the above polymerization for obtaining the polyamide component (P),it is possible to add polyols having hydroxyl group at the two molecularterminals in order to improve the compatibility with the polymericcomponent (T) possessing hydroxyl group at the two molecular terminals.

Examples of such polyols are, though not limited to the examples, butpreferable is the polyol with number-average molecular weight in therange from 500 to 5,000 and their glass transition temperature of notmore than 20° C. Examples are polyols, including for example,polyesters, aliphatic polyesters, polylactones, polycarbonates, and soon. Among them a polyol having a similar composition to the polymericcomponent (T) is particularly preferred.

The content of polyol having hydroxyl group at the two molecularterminals in the above polyamide component (P) is not particularlylimited, but preferably is in the range from 5 to 50 weight % of theabove polyamide component (P). With the content below 5%, the effect ofimproving compatibility with the polymeric component (T) is decreased.With the content exceeding 50 weight %, the melting point of theobtained polyamide component (P) is lowered, giving a bad influence onthe mechanical strength of the amide elastomer at high temperatures. Thecontent is most preferably in the range from 10 to 30 weight %.

The number-average molecular weight of the above polyamide component (P)is not limited in any manner, but preferably is in the range from 500 to5,000. With the molecular weight less than 500, the block property ofthe amide elastomer is decreased giving a bad influence on themechanical strength at high temperatures. With the molecular weightexceeding 5,000, the compatibility with the polymeric component (T) isdiminished, leading to smaller polymerization degrees for the obtainedamide elastomer, which results in the elastomer with insufficientmechanical strength. The molecular weight is more preferably in therange from 1,000 to 3,000.

The intrinsic viscosity of the above polyamide component (P) is notlimited in any manner, but preferably is 0.05 to 0.5. With the intrinsicviscosity less than 0.05, the block property of the amide elastomer isdecreased, giving a bad influence on the mechanical strength at hightemperatures. With the intrinsic viscosity larger than 0.5, thecompatibility with the polymeric component (T) is diminished, leading tosmaller polymerization degrees for the obtained amide elastomer, whichresults in the elastomer with insufficient mechanical strength. Theintrinsic viscosity is more preferably in the range from 0.1 to 0.3.

In the part III of the present invention, the polymeric component (T)having hydroxyl group at the two molecular terminals is defined to havethe glass transition temperature of not more than 20° C. and thenumber-average molecular weight in the range from 500 to 5,000. Anexample of such polymeric component (T) is the one similar to theexample in part I of the present invention.

The amide elastomer according to the part III of the present inventionis defined as the block-copolymer of the above polyamide component (P)and the polymeric component (T) possessing hydroxyl group at the twomolecular terminals, which are connected with the isocyanate component(Q).

In order to obtain the above amide elastomer, which is block copolymer,produced by binding above polyamide component (P) with the polymericcomponent (T) possessing hydroxyl group at the two molecular terminalswith the diisocyanate (Q), the polyamide component (P) and the polymericcomponent (T) possessing hydroxyl group at the two molecular terminalsbind with each other by the diisocyanate compound (Q′) expressed by thegeneral formula (64).

Usually the above polyamide component (P) may preferably contain aminogroup at the two molecular terminals, but may contain carboxyl group oramino group partly. The above polymeric component (T) contains hydroxylgroup at the two molecular terminals usually, but may contain carboxylgroup or amino group partly. When the two molecular terminals of the twocomponents reacting with the diisocyanate compound (Q′) are bothhydroxyl group, the two components may be connected with the isocyanatecomponent (Q) expressed by the following general formula (58). When onemolecular end is hydroxyl group and the other end is amino group, on theother hand, they are connected with the isocyanate component (Q)expressed by the general formula (59). In the latter case the elastomermay contain a fragment connected with the isocyanate component expressedby the following general formula (59).

When the two molecular terminals for the polyamide component (P) and thepolymeric component (T) both comprise amino group, the elastomer maycontain a small portion in which the two components are connected witheach other by the isocyanate component expressed by the followinggeneral formula (65). When terminal functional group is amino group andthe other end is carboxyl group, the elastomer may contain a smallportion in which the two components are connected with each other by theisocyanate component expressed by the general formula (66).

When the two terminal functional group for the polyamide component (P)and the polymeric component (T) both comprise carboxyl group, theelastomer may contain a small portion in which the two components areconnected with each other by the isocyanate component expressed by thefollowing general formula (67). When one molecular end is carboxyl groupand the other end is hydroxyl group, the elastomer may contain a smallportion in which the two components are connected with the isocyanatecomponent expressed by the general formula (68),—O—CO—NH—R¹⁰′—NH—CO—O—  (58)—O—CO—NH—R¹¹′—NH—CO—NH—  (59)—OCN—R¹⁷′—NCO—  (64)—NH—CO—NH—R¹⁸′—NH—CO—NH—  (65)—NH—CO—NH—R¹⁹′—NH—CO—  (66)—CO—NH—R²⁰′—NH—CO—  (67)—CO—NH—R²¹′—NH—CO—O—  (68)

In these formula (58), (59), (64), (65), (66), (67) and (68) R¹⁰′, R¹¹′,R¹⁷′, R¹⁸′, R¹⁹′, R²⁰′, and R²¹′ denote an alkylene group of 2 to 15carbons, —C₆H₄— (phenylene group), —C₆H₄—CH₂—, or —C₆H₄—CH₂—C₆H₄—)group.

R¹⁰′, R¹¹′, R¹⁷′, R¹⁸′, R¹⁹′, R²⁰′, and R²¹′ may be a compositefunctional group of the above groups.

Examples of the above diisocyanate compounds (Q′) are similar to thediisocyanate compound (U′) in the present part I of the presentinvention.

The amide elastomer according to the part III of the present inventioncomprises 50 to 2,000 parts by weight of the polymeric component (T),and 10 to 100 parts by weight of the isocyanate component (Q) relativeto 100 parts by weight of the polyamide component (P).

With the polymeric component (T) less than 50 parts by weight, theobtained amide elastomer loses sufficient elasticity. With the polymericcomponent (T) exceeding 2,000 parts by weight, the obtained amideelastomer loses sufficient mechanical strength. The content ispreferably in the range from 200 to 1,000 parts by weight.

With the isocyanate component (Q) less than 10 parts by weight, theobtained amide elastomer does not reach the sufficient molecular weight,leading to inferior mechanical strength. With the isocyanate component(Q) exceeding 100 parts by weight, the obtained amide elastomer losessufficient elasticity. The content is preferably in the range from 30 to70 parts by weight.

In the production method of amide elastomer according to the part III ofthe present invention, the production method of the amide elastomer ischaracterized by comprising the following two processes. {circle around(1)} Production of prepolymer by the reacting the polymeric component(T) possessing hydroxyl group at the two molecular terminals with thediisocyanate compound (Q′), and {circle around (2)} The process ofreacting the above prepolymer with the polyamide component (P).

The advantages of the part III invention are found in the following twopoints.

(1) Usually diffent polymeric components are not mutually compatible,and difficult to react with each other. When the polymeric component (T)and the polyamide component (P) used in the part III of the presentinvention are reacted simultaneously with the diisocyanate compound(Q′), usually the simultaneous reaction of the three components yields ablended mixture of two polymeric species, inhibiting the production ofblock copolymer. Instead, the polymer growth proceeds for the twocomponents such as the polymeric components (T) with the diisocyanatecompound (Q′), or the polyamide components (P) with the diisocyanatecompound (Q′). According to the part III of the present invention,however, the terminal isocyanate group in the prepolymer comprising thepolymeric component (T) is reacted securely with the polyamide component(P), yielding the block copolymer. In order to enhance the reactivity inthis case, the reaction apparatus and the reaction temperature are thecritical factors.

(2) In the second process, an excess molar amount of the polyamidecomponent (P) is reacted with the prepolymer. This works to yield blockcopolymers, of which the molecular terminals are sealed with the hardsegment, that is, the polyamide component.

The physical property of the product thus obtained as an elastomervaries to a large extent depending on the terminal kinds of the blockcopolymer. When the terminal is the soft segment of the polymericcomponent (T), this segment does not contribute to the expression ofrubber elasticity, but lowers the melting point of the crystalline hardsegment, inducing inferior creep resistance and mechanical strength athigh temperatures. When the terminal is the hard segment, on the otherhand, it is expected to improve the creep resistance and mechanicalstrength at high temperatures. The production method of thethermoplastic elastomer according to the part III of the presentinvention is suited for obtaining block copolymers, of which themolecular terminal is sealed with the hard segment that is expected toimprove the creep resistance and mechanical strength at hightemperatures.

The illustrative embodiments of the production method according to thepart III of the present invention are described hereinafter in detail.

In the above first process, it is preferable to react the polymericcomponent (T) with an excess amount of the diisocyanate compound (Q′).The molar amount of the diisocyanate compound (Q′) to the polymericcomponent (T) is most preferably in the range from 1.1 to 2.2 times.With the ratio below 1.1 times, the two molecular terminals of theobtained prepolymer are not completely converted to isocyanate group,which may inhibit the reaction in the second process. With the ratioexceeding 2.2 times, a part of the diisocyanate compound (Q′) is leftunreacted after the reaction, which may cause side reactions in thesecond process. The molar ratio is more preferably in the range from 1.2to 2.0 times.

The reaction temperature in the above first process is preferably in therange from 100 to 240° C. With the temperature below 100° C., thereaction may not proceed sufficiently. With the temperature exceeding240° C., the polymeric component (T) starts to decompose. The reactiontemperature is more preferably in the range from 120 to 160° C.

In the above second process, the obtained prepolymer is reacted with thepolyamide component (P) having a molar ratio of 0.9 to 3.0 times. Inorder to obtain block copolymers, of which the molecular terminals aresealed with the hard segment, that is the polyamide component, theprepolymer may be reacted preferably with an excess molar amount of thepolyamide component (P). The molar ratio of the polyamide component (P)to the prepolymer is preferably in the range from 1.2 to 3.0 times. Whenthe molar ratio is below less than 1.2 times, the reaction may partlyyield block copolymers having the soft segment in the molecularterminal. With the molar ratio exceeding 3.0 times, the elasticity ofthe obtained amide elastomer becomes inferior. The molar ratio is morepreferably in the range from 1.25 to 2.0 times.

It is possible to control the structure of the obtained block copolymersby changing the composition ratio of the polyamide component (P) and thepolymeric component (T). If the hard segment is referred to as A and thesoft segment is referred to as B, block copolymers of ABA type areobtained when the molar ratio of the polyamide component (P) to theprepolymer is 2.0 times. When the ratio is 1.5 times, block copolymersof ABABA type are obtained. And when the ratio is 1.25 times, blockcopolymers of ABABABABA type are obtained.

The amide elastomer having significantly improved creep resistance andmechanical strength at high temperatures may be prepared by reacting ablock copolymer, of which molecular terminals are sealed with the hardsegment of the polyamide component, with the diisocyanate compound (Q′)followed by further molecular weight treatment.

If the molecular terminal of the hard segment is not the requisite, itis preferable, for obtaining the amide elastomer of high molecularweight, to react the prepolymer with the polyamide component (P) in amolar ratio of 0.9 to 1.2 times. When the molar ratio is below 0.9 timeor exceeds 1.2 times, it becomes difficult to increase the molecularweight.

In the case wherein the two molecular terminals of the prepolymeremployed in the second process are not completely converted toisocyanate group, the amide elastomer with high molecular weight may beobtained by the following method. The polyamide component (P) is firstreacted with an excess molar amount of diisocyanate compound (Q′)yielding another polyamide compound (P) having isocyanate group at thetwo molecular terminals. Then this product is further reacted with theabove prepolymer yielding the amide elastomer of high molecular weight.In the above series of reactions, the molar amount of diisocyanatecompound (Q′) is preferably in the range from 0.9 to 1.2 times to thesum of the polymeric component (T) and the polyamide component (P). Whenthe molar ratio is below 0.9 time or exceeds 1.2 times, it becomesdifficult to increase the molecular weight.

In the above second process, the reaction temperature is preferably inthe range from 180 to 280° C. With the temperature below 180° C., thepolyamide component does not completely meet. As a result, the reactiondoes not proceed smoothly, leading to lowered molecular weight for theobtained product. With the temperature exceeding 280° C., the prepolymerand the diisocyanate compound (Q′) starts to decompose, thus it isdifficult to obtain polymers of insufficient mechanical strength. Thereaction temperature is more preferably in the range from 200 to 260° C.

It is possible to employ catalysts for the above reaction in theproduction method according to the part III of the present invention.Examples of the above catalysts are similar to the catalysts describedin the part I of the present invention.

The above reaction is preferably carried out in bulk. With this reactionmethod, the reactivity of the second process is improved significantly.With regard to the reaction apparatus, an extruder may be employed.

As the above extruder, a bi-axial extruder wherein two axes rotate inthe same direction is preferably used. By using this apparatus, thereactivity for the second process is particularly improved. A tandemextruder is preferably employed for carrying out for the first processand the second process continuously.

It is possible to use the aforementioned stabilizers in the productionmethod according to the part III of the present invention. It is alsopossible to add above-mentioned stabilizers to the amide elastomerproduced by the method according to the part III of the presentinvention.

The part IV of the present invention relates to an amide elastomerproduced by the production method of amide elastomer according to thepart III of the present invention. The amide elastomer according to thepart IV of the present invention is produced by the production method ofamide elastomer according to the part III of the present invention. Itexhibits high block property for the hard segment component and the softsegment component as well as the excellent elasticity and the mechanicalcharacteristics at high temperatures, especially the settling resistanceat high temperatures.

During or after the production, it is also possible to add additives tothe amide elastomer according to the part IV of the present invention aslong as the practical quality of the elastomer is not impaired. Examplesof the additives include fibers, inorganic fillers, flame-retardants, UVlight absorbers, anti-static agents, inorganic substances, and salts ofhigher fatty acids. They may be used singly or in mixed form of morethan two kinds.

The properties of the amide elastomer according to the part IV of thepresent invention may be modified by blending other thermoplasticresins, or rubber components.

The amide elastomer according to the part IV of the present inventionmay be shaped to molded products using methods such as press molding,extrusion molding, injection molding, or blow molding. The moldingtemperature varies depending on the melting point of the employedelastomer and the molding method, but is preferably in the range from160 to 280° C. With the molding temperature below 160° C., theflowability of the amide elastomers becomes low, leading to thenon-homogeneous molded products. With the molding temperature exceeding280° C., the obtained elastomer starts to decompose, yielding productswith insufficient mechanical strength.

The amide elastomer according to the part IV of the present inventionmay be preferably employed for molded parts of automobile, electric andelectronic parts, industrial parts, sport goods, and medical goods.

In addition, the thermoplastic elastomer according to the part IV of thepresent invention may be favorably employed for elastomer fibers,elastomer sheets, composite sheets, films, composite films, foams,hot-melt adhesives, binders, and polymer-alloys together with otherresins.

The amide elastomer according to the part IV of the present inventionhas excellent elasticity and physical properties at high temperaturesdue to the following reasons.

Usually different polymeric components are not mutually compatible, anddifficult to react with each other. When the polymeric component (T)belonging to the soft segment component and the polyamide component (P)belonging to the hard segment component are bonded with each other bycontrolling the reaction with the diisocyanate compound (Q′). As theresult, an amide elastomer is obtained possessing especially high blockproperty for the hard segment and the soft segment.

The amide elastomer exhibits its character as an elastomer due to thecross-linking points formed by the polyamide component. As the amideelastomer according to the part IV of the present invention comprisesthe polyamide rich section and the soft segment rich section, thepolyamide section goes to crystallize more readily than ordinary amideelastomers having a similar elasticity. As a result, rigid cress-linkingpoints are formed, yielding elastomer materials having superiormechanical characteristics at high temperatures. The presence of softsegment rich section increases the molecular weight betweencross-linking points, which leads to elastomer materials with superiorelasticity.

While the illustrative embodiments of the present invention have beendescribed hereinafter in detail, it is not intended that the scope ofthe present invention is limited to the examples and descriptions.Measurements for various physical characteristics were carried out byemploying the following methods.

Number-average molecular weight: Gel permeation chromatography (HLC 8020series, produced by TOSOH)

-   -   Column: Shodex HFIP 806M (in duplicate)    -   Solvent: hexafluoro-isopropanol (with 0.005N sodium        trifluoroacetate)    -   Standard: polymethyl methacrylate

Acid value for polyester: A sample is dissolved in a mixed solvent ofbenzyl alcohol/chloroform followed by the neutralization titration usingphenol red as the indicator.

Hydroxyl value for polyester: a sample and succinic anhydride aredissolved in a mixed solvent of nitrobenzene/pyridine for 10 hours.Methanol is added to the reaction mixture for precipitation. Theobtained reaction product is treated for the above acid valuemeasurement to yield the hydroxyl value.

The certified values of the manufacturer are adopted for the acid valueand hydroxyl value for the polyether, and isocyanate value (NCO value)for the isocyanate compound. Glass transition temperature: Measured witha viscoelasticity spectrometer (RSA-II, produced by RheometricScientific F.E.) with the raising rate of temperature at 3° C./min,frequency at 1.61 Hz, strain at 0.05%, sample: rectangle (size of 0.5 mmthick and 3 mm width).

Melting point: measured by differential scanning calorimeter (DSC) withthe raising rate of temperature at 10° C./min.

Surface rigidity: measured with the A-type spring at 23° C., accordingto JIS K6301.

Tensile characteristics: measured the tensile strength and the strain atroom temperature according to JIS K6301.

Permanent compression strain: measured compression strain at 100° C.with 25% according to JIS K6301.

Moisture permeability: measured film with a 100 micron thick accordingto JIS Z0208 and ASTM F372-73.

Light resistance: A sheet with 1 mm thick is exposed to light in carbonarc type Fade tester with black panel temperature of 63° C. for 80hours. The yellowness, i.e. yellowing value was measured (according toJIS K7105) by color-difference meter (Color Analyzer, TC-1800 MK-II,produced by Tokyo Denshoku CO.) together with the surface rigidity, andcalculated from the difference between before and after the exposure.Solubility was measured by the following method.

An elastomer sample of 15 g was mixed with 85 g of N,N-dimethylformamide (DMF) and stirred at 120° C. for 1 hour.

-   -   ◯: soluble    -   Δ: soluble with difficulty    -   X: hardly soluble

The stability of the solution was measured by the following method.

The above solution for the solubility measurement was kept at 80° C. for1 hour for the judgement of stability.

-   -   ◯: stable    -   Δ: coagulates as sol    -   X: quick formation of insoluble precipitates

PREFERRED EMBODIMENTS OF THE INVENTION REFERENCE EXAMPLE 1 Synthesis ofPolyester (b-1)

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,102 parts of 1,4-butane diol, 0.3 parts of tetrabutyl titanate ascatalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reuced pressure.The polymerization system reached less than 2 Torr in 15 minutes after astart of reducing pressure. It was kept for more 10 minutes for thepolycondensation reaction, yielding finally 113 parts (wt) of polyesterof white color. This polyester (b-1) was analyzed to have thenumber-average molecular weight of 2,000, the acid value and thehydroxyl value of 5.0 (micro-eq/g) and 1,000 (micro-eq/g) respectively.

REFERENCE EXAMPLE 2

Synthesis of Polyester (b-2)

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,102 parts of 1,4-butane diol, 48 parts of polytetramethylene glycol(produced by BASF, PTHF1000, number-average molecular weight in about1,000), 0.3 parts of tetrabutyl titanate as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reducedpressure. The polymerization system reached less than 2 Torr in 15minutes after a start of reducing pressure. It was kept for more 30minutes for the polycondensation reaction, yielding finally 160 parts(wt) of polyester of white color. This polyester (b-2) was analyzed tohave the number-average molecular weight of 5,000, the acid value andthe hydroxyl value of 5.0 (micro-eq/g) and 400 (micro-eq/g)respectively.

REFERENCE EXAMPLE 3

Synthesis of Polyester (b-3)

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,38 parts of dimethyl adipate, 102 parts of 1,4-butane diol, 0.3 parts oftetrabutyl titanate as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reducedpressure. The polymerization system reached less than 2 Torr in 15minutes after a start of reducing pressure. It was kept for more 10minutes for the polycondensation reaction, yielding finally 128 parts(wt) of polyester of white color. This polyester (b-3) was analyzed tohave the number-average molecular weight of 2,200, the acid value andthe hydroxyl value of 6.0 (micro-eq/g) and 900 (micro-eq/g)respectively.

REFERENCE EXAMPLE 4

Synthesis of Polyester (b-4)

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,83 parts of 1,4-butane diol, 30 parts of cyclohexane dimethanol, 0.3parts of tetrabutyl titanate as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reducedpressure. The polymerization system reached less than 2 Torr in 15minutes after a start of reducing pressure. It was kept for more 5minutes for the polycondensation reaction, yielding finally 136 parts(wt) of polyester of white color. This polyester (b-4) was analyzed tohave the number-average molecular weight of 1,000, the acid value andthe hydroxyl value of 4.0 (micro-eq/g) and 1,900 (micro-eq/g)respectively.

REFERENCE EXAMPLE 5

Synthesis of Polyester (b-5)

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,43 parts of dimethyl isophthalate, 156 parts of 1,4-butane diol, 0.3parts of tetrabutyl titanate as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reducedpressure. The polymerization system reached less than 2 Torr in 15minutes after a start of reducing pressure. It was kept for more 15minutes for the polycondensation reaction, yielding finally 120 parts(wt) of polyester of white color. This polyester (b-5) was analyzed tohave the number-average molecular weight of 3,200, the acid value andthe hydroxyl value of 7.0 (micro-eq/g) and 625 (micro-eq/g)respectively.

REFERENCE EXAMPLE 6

Synthesis of Polyester (b-6)

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,11 parts of dimethyl isophthalate, 103 parts of 1,4-butane diol, 17parts of cyclohexane dimethanol, 0.3 parts of tetrabutyl titanate ascatalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reducedpressure. The polymerization system reached less than 2 Torr in 15minutes after a start of reducing pressure. It was kept for more 10minutes for the polycondensation reaction, yielding finally 120 parts(wt) of polyester of white color. This polyester (b-6) was analyzed tohave the number-average molecular weight of 2,600, the acid value andthe hydroxyl value of 7.0 (micro-eq/g) and 770 (micro-eq/g)respectively.

EXAMPLE 1

An elastomer composition comprising 300 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,87.5 parts of 4,4′-diphenylmethane diisocyanate, which corresponds tothe poly-isocyanate compound (c) having the NCO value of 8,000(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-1) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolten and mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention comprising thepolyether component in 62 weight % having the carbon/oxygen atomic ratioof 2.0, and having the glass transition temperature of −30° C.

Meanwhile the NCO value means the number of NCO molecular terminals per1 g elastomer, and is defined by the unit of 1/MX, where MX is thenumber of isocyanate radicals.

The obtained elastomer pellets were molded into 2 mm thick sheets and100 micrometer thick sheets through the press molding (at 220° C.), andmeasured of various properties. The solubility measurements were carriedout using the pellets in situ. The results are summarized in Table 1.

EXAMPLE 2

The pellets of the thermoplastic elastomer were prepared as in Example 1except that 286 parts by weight of polyethylene glycol and 83 parts byweight of 4,4′-diphenylmethane diisocyanate were employed. The obtainedpellets were formed into 2 mm thick sheets and 100 micrometer thicksheets with the press molding machine(at 230° C.), and various physicalproperties of the sheets were measured. A measurement of solubility wascarried out using the pellets themselves. The results are summarized inTable 1.

EXAMPLE 3

The pellets of the thermoplastic elastomer were prepared as in Example 1except that 240 parts by weight of polyethylene glycol having thenumber-average molecular weight of 1,000, the hydroxyl value of 2,000(micro-eq/g), and the acid value of 0 (micro-eq/g) was employed as thepolyether compound (a) together with 60 parts by weight ofpolytetrametylene glycol having the number-average molecular weight of1,000, the hydroxyl value of 2,000 (micro-eq/g), and the acid value of 0(micro-eq/g). The obtained pellets were formed into 2 mm thick sheetsand 100 micrometer thick sheets with the press molding machine (at 230°C.) and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 1.

EXAMPLE 4

The pellets of the thermoplastic elastomer were prepared as in Example 1except that 210 parts (wt) of polyethylene glycol having thenumber-average molecular weight of 1,000, the hydroxyl value of 2,000(micro-eq/g), and the acid value of 0 (micro-eq/g) were employed as thepolyether compound (a) together with 90 parts of a polyether, which wasprepared by the equi-molar copolymerization of ethylene oxide andtetrahydrofuran, having the number-average molecular weight of 1,000,the hydroxyl value of 2,000 (micro-eq/g), and the acid value of 0(micro-eq/g). The obtained pellets were formed into 2 mm thick sheetsand 100 micrometer thick sheets with the press molding machine (at 230°C.), and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 1.

EXAMPLE 5

The pellets of the thermoplastic elastomer were prepared as in Example 1except that 450 parts by weight of polyethylene glycol having thenumber-average molecular weight of 1,500, the hydroxyl value of 1,300(micro-eq/g), and the acid value of 0 (micro-eq/g) was employed as thepolyether compound (a) together with 87.5 parts by weight of4,4′-diphenylmethane diisocyanate. The obtained pellets were formed into2 mm thick sheets and 100 micrometer thick sheets with the press moldingamchine (at 220° C.), and various physical properties of the sheets weremeasured. A measurement of solubility was carried out using the pelletsthemselves. The results are summarized in Table 1.

EXAMPLE 6

An elastomer composition comprising 160 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively, 45parts of 4,4′-diphenylmethane diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 8,000 (micro-eq/g),was led into a bi-axial extruder (produced by Toshiba Machinery, L/D=58)through its first barrel, supplying at the same time 100 parts of thepolyester (b-2) mentioned hereinabove through the fifth barrel of thesame extruder using the compulsory side, and was molten and mixedtogether at 200° C. The product in pellet form was the thermoplasticelastomer of the present invention.

The obtained elastomer pellets were formed into 2 mm thick sheets and100 micrometer thick sheets with the press molding machine(at 220° C.),and various properties of the sheets were measured. A measurement ofsolubility was carried out using the pellets themselves. The results aresummarized in Table 1.

EXAMPLE 7

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,102 parts of 1,4-butane diol, 170 parts of polyethylene glycol havingthe number-average molecular weight of 1,000, 0.3 parts of tetrabutyltitanate as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reducedpressure. The polymerization system reached less than 2 Torr in 20minutes after a start of reducing pressure. It was kept for more 6minutes for the polycondensation reaction, yielding finally 283 parts(wt) of the thermoplastic elastomer of the present invention.

The obtained elastomer was formed into 2 mm thick sheets and 100micrometer thick sheets with the press molding machine (at 230° C.), andvarious properties of the sheets were measured. A measurement ofsolubility was carried out using the pellets themselves. The results aresummarized in Table 1.

EXAMPLE 8

An elastomer composition comprising 273 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,79.5 parts of 4,4′-diphenylmethane diisocyanate, which corresponds tothe poly-isocyanate compound (c) having the NCO value of 8,000(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-3) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolten and mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention.

The obtained elastomer pellets were formed into 2 mm thick sheets and100 micrometer thick sheets with the press molding machine(at 220° C.),and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 1.

EXAMPLE 9

An elastomer composition comprising 600 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,175 parts of 4,4′-diphenylmethane diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 8,000 (micro-eq/g),was led into a bi-axial extruder (produced by Toshiba Machinery, L/D=58)through its first barrel, supplying at the same time 100 parts of thepolyester (b-4) mentioned hereinabove through the fifth barrel of thesame extruder using the compulsory side feeder, and was molten and mixedtogether at 200° C. The product in pellet form was the thermoplasticelastomer of the present invention.

The obtained elastomer pellets were molded into 2 mm thick sheets and100 micrometer thick sheets with the press molding machine(at 220° C.),and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 1.

EXAMPLE 10

An elastomer composition comprising 156 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively, 47parts of 4,4′-diphenylmethane diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 8,000 (micro-eq/g),was led into a bi-axial extruder (produced by Toshiba Machinery, L/D=58)through its first barrel, supplying at the same time 100 parts of thepolyester (b-5) mentioned hereinabove through the fifth barrel of thesame extruder using the compulsory side feeder, and was molten and mixedtogether at 200° C. The product in pellet form was the thermoplasticelastomer of the present invention.

The obtained elastomer pellets were formed into 2 mm thick sheets and100 micrometer thick sheets with the press molding machine (at 220° C.),and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 1.

EXAMPLE 11

An elastomer composition comprising 231 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively, 67parts of 4,4′-diphenylmethane diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 8,000 (micro-eq/g),was led into a bi-axial extruder (produced by Toshiba Machinery, L/D=58)through its first barrel, supplying at the same time 100 parts of thepolyester (b-6) mentioned hereinabove through the fifth barrel of thesame extruder using the compulsory side feeder, and was molten and mixedtogether at 200° C. The product in pellet form was the thermoplasticelastomer of the present invention.

The obtained elastomer pellets were formed into 2 mm thick sheets and100 micrometer thick sheets with the press molding machine(at 220° C.),and various properties of the sheets were measured. A measurement ofsolubility was carried out using the pellets themselves. The results aresummarized in Table 1.

COMPARATIVE EXAMPLE 1

The pellets of the thermoplastic elastomer were prepared as in Example 1except that 50 parts by weight of polyethylene glycol was employed and25 parts by weight of 4,4′-diphenylmethane diisocyanate were employed.The obtained pellets were formed into 2 mm thick sheets and 100micrometer thick sheets with the press molding machine(at 220° C.), andvarious physical properties of the sheets were measured. A measurementof solubility was carried out using the pellets themselves. The resultsare summarized in Table 1.

COMPARATIVE EXAMPLE 2

The pellets of the thermoplastic elastomer were prepared as in Example 1except that 300 parts by weight of polytetramethylene glycol having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,was employed as the polyether compound (a). The obtained pellets wereformed into 2 mm thick sheets and 100 micrometer thick sheets with thepress molding machine (at 220° C.), and various physical properties ofthe sheets were measured. The results are summarized in Table 1.

COMPARATIVE EXAMPLE 3

The pellets of the thermoplastic elastomer were prepared as in Example 1except that 360 parts by weight of polyethylene glycol having thenumber-average molecular weight of 600, the hydroxyl value of 3,300(micro-eq/g), and the acid value of 0 (micro-eq/g) was employed as thepolyether compound (a) together with 162.5 parts by weight of4,4′-diphenylmethane diisocyanate having the NCO value of 8,000(micro-eq/g). The obtained pellets were formed into 2 mm thick sheetsand 100 micrometer thick sheets with the press molding machine (at 220°C.), and various physical properties of the sheets were measured. Theresults are summarized in Table 1.

COMPARATIVE EXAMPLE 4

The pellets of the thermoplastic elastomer were prepared as Example 1except that 180 parts by weight of polyethylene glycol having thenumber-average molecular weight of 1,000, the hydroxyl value of 2,000(micro-eq/g), and the acid value of 0 (micro-eq/g) was employed as thepolyether compound (a) together with 120 parts by weight ofpolytetramethylene glycol having the number-average molecular weight of1,000, the hydroxyl value of 2,000 (micro-eq/g), and the acid value of 0(micro-eq/g). The obtained pellets were formed into 2 mm thick sheetsand 100 micrometer thick sheets with the press molding machine (at 230°C.), and various physical properties of the sheet were mearured. Theresults are summarized in Table 1.

COMPARATIVE EXAMPLE 5

The pellets of the thermoplastic elastomer were prepared as in Example 1except that all of the polyether compound (a), the polyester compound(b), and the poly-isocyanate compound (c) were blended simultaneouslyand led through the first barrel, but only as clay-like product wasobtained without the thermoplastic elastomer of the present inventionobtained.

TABLE 1 Example 1 2 3 4 5 6 7 8 9 10 11 Thermoplastic elastomer Contentof polyether 62 61 62 62 70 52 60 60 69 51 58 component (wt %) C/O ratiofor 2 2 2.4 2.3 2 2 2 2 2 2 2 polyether component Glass transition −30−30 −40 −45 −45 −25 −42 −30 −30 −30 −30 temperature (° C.) Physicalproperty of Thermoplastic elastomer Melting point (° C.) 185 190 185 185175 185 155 158 148 155 160 Surface rigidity (JIS A) 75 77 75 75 70 9091 75 68 77 72 Tensile strength (kgf/cm2) 200 170 220 200 160 280 100170 150 180 160 Elongation (%) 1200 1000 1300 1100 1400 900 650 12002000 1500 1600 Permanent strain of 55 47 55 56 57 51 98 73 79 68 73Compression (100° C., %) Moisture permeability (g/cm2/24 hr) 9000 85007000 6800 10000 6000 10200 8200 8000 7800 8600 (ASTM F372-73) Moisturepermeability (g/cm2/24 hr) 3700 3600 3400 3400 3800 3300 3800 3600 36003500 3600 (JIS Z0208) Solubility x x x x Δ x Δ ∘ ∘ ∘ ∘ Stability x x x xΔ x Δ ∘ ∘ ∘ ∘ Comparative example 1 2 3 4 5 Thermoplastic elastomerContent of polyether 29 62 58 62 62 component (wt %) C/O ratio for 2 4 22.8 2 polyether component Glass transition −20 −50 −10 −47 — temperature(° C.) Physical property of Thermoplastic elastomer Melting point (° C.)200 185 180 185 Clay- Surface rigidity (JIS A) 98 75 80 75 like Tensilestrength (kgf/cm2) 350 220 350 230 prodt. Elongation (%) 600 1400 7001350 Permanent strain of 50 54 55 55 Compression (100° C., %) Moisturepermeability (g/cm2/24 hr) 2000 1000 2500 3500 (ASTM F372-73) Moisturepermeability (g/cm2/24 hr) 1100 600 1400 1800 (JIS Z0208) Solubility x xx x Stability x x x x

EXAMPLE 12

An elastomer composition comprising 300 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,62.3 parts of hexamethylene diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 11,900(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-1) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolten and mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention.

The obtained elastomer pellets were formed into 1.2 mm thick sheets and100 micrometer thick sheets with the press molding machine(at 220° C.),and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 2.

EXAMPLE 13

The pellets of the thermoplastic elastomer were prepared as in Example12 except that 286 parts by weight of polyethylene glycol was employedtogether with 59 parts of hexamethylene diisocyanate and 0.3 parts oftin octanoate. The obtained pellets were formed into 1.2 mm thick sheetsand 100 micrometer thick sheets with the press molding machine (at 230°C.), and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 2.

EXAMPLE 14

The pellets of the thermoplastic elastomer were prepared as in Example12 except that 240 parts by weight of polyethylene glycol having thenumber-average molecular weight of 1,000, the hydroxyl value of 2,000(micro-eq/g), and the acid value of 0 (micro-eq/g) was employed as thepolyether compound (a) together with 60 parts by weight ofpolytetramethylene glycol having the number-average molecular weight of1,000, the hydroxyl value of 2,000 (micro-eq/g), and the acid value of 0(micro-eq/g). The obtained pellets were formed into 1.2 mm thick sheetsand 100 micrometer thick sheets with the press molding machine (at 230°C.), and various physical properties of the sheets were measured. Ameasurement of solubility was carried out using the pellets themselves.The results are summarized in Table 2.

EXAMPLE 15

The pellets of the thermoplastic elastomer were prepared as in Example12 except that 210 parts by weight of polyethylene glycol having thenumber-average molecular weight of 1,000, the hydroxyl value of 2,000(micro-eq/g), and the acid value of 0 (micro-eq/g) was employed as thepolyether compound (a) together with 90 parts of a polyether, which wasprepared by the equi molar copolymerization of ethylene oxide andtetrahydrofuran, having the number-average molecular weight of 1,000,the hydroxyl value of 2,000 (micro-eq/g), and the acid value of 0(micro-eq/g) in 60 parts by weight. The obtained pellets were formedinto 2 mm thick sheets and 100 micrometer thick sheets with the pressmolding machine(at 230° C.), and various physical properties of thesheets were measured. A measurement of solubility was carried out usingthe pellets themselves. The results are summarized in Table 2.

EXAMPLE 16

The pellets of the thermoplastic elastomer were prepared as in Example12 except that 450 parts by weight of polyethylene glycol having thenumber-average molecular weight of 1,500, the hydroxyl value of 1,300(micro-eq/g), and the acid value of 0 (micro-eq/g) was employed as thepolyether compound (a) together with 62.3 parts by weight ofhexamethylene diisocyanate. The obtained pellets were formed into 1.2 mmthick sheets and 100 micrometer thick sheets with the press moldingmachine (at 220° C.), and various physical properties of the sheets weremeasured. A measurement of solubility was carried out using the pelletsthemselves. The results are summarized in Table 2.

EXAMPLE 17

An elastomer composition comprising 160 parts of polyethylene glycol,which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively, 32parts of hexamethylene diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 11,900(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-2) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and moltenand mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention. The obtained elastomerpellets were formed into 1.2 mm thick sheets and 100 micrometer thicksheets through the press molding machine(at 220° C.), and variousphysical properties of the sheets were measured. A measurement ofsolubility was carried out using the pellets themselves. The results aresummarized in Table 2.

EXAMPLE 18

A reaction system comprising 100 parts of dimethyl terephthalate, 102parts of 1,4-butane diol, 170 parts of polyethylene glycol having thenumber-average molecular weight of 1,000, 0.3 parts of tetrabutyltitanate as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed by measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. in 20 minutes and reducedpressure. The polymerization system reached less than 2 Torr in 20minutes after a start of reducing pressure. It was kept for more 6minutes for the polycondensation reaction, yielding finally 283 parts(wt) of the thermoplastic elastomer of the present invention.

The obtained elastomer was formed into 2 mm thick sheets and 100micrometer thick sheets with the press molding machine (at 230° C.), andvarious physical properties of the sheets were measured. A measurementof solubility was carried out using the pellets themselves. The resultsare summarized in Table 2.

EXAMPLE 19

An elastomer composition comprising 273 parts of polyethylene glycol,which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,56.6 parts of hexamethylene diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 11,900(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-3) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolten and mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention. The obtained elastomerpellets were formed into 1.2 mm thick sheets and 100 micrometer thicksheets with the press molding machine(at 220° C.), and various physicalproperties of the sheets were measured. A measurement of solubility wascarried out using the pellets themselves. The results are summarized inTable 2.

EXAMPLE 20

An elastomer composition comprising 600 parts of polyethylene glycol,which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,124.6 parts of hexamethylene diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 11,900(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-4) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolten and mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention.

The obtained elastomer pellets were formed into 1.2 mm thick sheets and100 micrometer thick sheets with the press molding machine (at 220° C.),and various physical properties of the sheets were measured. Ameasurement of the solubility was carried out using the pelletsthemselves. The results are summarized in Table 2.

EXAMPLE 21

An elastomer composition comprising 156 parts of polyethylene glycol,which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively, 34parts of hexamethylene diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 11,900(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the above polyester (b-5) through the fifth barrel of thesame extruder using the compulsory side feeder for the molten blendingat 200° C., yielding finally pellets of the thermoplastic elastomeraccording to the present invention.

The obtained elastomer pellets were molded into 1.2 mm thick sheets and100 micrometer thick sheets through the press molding (at 220° C.), andmeasured of various properties. The solubility measurements were carriedout using the pellets in situ. The results are summarized in Table 2.

EXAMPLE 22

An elastomer composition comprising 231 parts of polyethylene glycol,which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively, 48parts of hexamethylene diisocyanate, which corresponds to thepoly-isocyanate compound (c) having the NCO value of 11,900(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-6) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolten and mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention.

The obtained elastomer pellets were formed into 1.2 mm thick sheets and100 micrometer thick sheets with the press molding machine (at 220° C.).The various physical properties of the sheet were mearured. Ameasurement of the solubility was carried out using the pelletsthemselves. The results are summarized in Table 2.

COMPARATIVE EXAMPLE 6

The example 12 was repeated except that polyethylene glycol was employedin 50 parts together with 25 parts of 4,4′-diphenylmethane diisocyanate,yielding finally pellets of the thermoplastic elastomer. The obtainedpellets were formed into 1.2 mm thick sheets and 100 micrometer thicksheets with the press molding method (at 220° C.) for the measurementsof various properties. The results are summarized in Table 2.

COMPARATIVE EXAMPLE 7

The pellets of the thermoplastic elastomer were prepared as in Example12 except that 300 parts by weight of polytetramethylene glycol havingthe number-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,was employed as the polyether compound (a) together with 87.5 parts of4,4′-diphenylmethane diisocyanate. The obtained pellets were formed into1.2 mm thick sheets and 100 micrometer thick sheets with the pressmolding machine (at 220° C.). The various physical properties of thesheet were mearured. The results are summarized in Table 2.

COMPARATIVE EXAMPLE 8

The pellets of the thermoplastic elastomer were prepared as in Example12 except that 360 parts by weight of polyethylene glycol having thenumber-average molecular weight of 600, the acid value and the hydroxylvalue of 0 (micro-eq/g) and 3,300 (micro-eq/g) respectively, wasemployed as the polyether compound (a) together with 162.5 parts of4,4′-diphenylmethane diisocyanate having the NCO value of 8,000(micro-eq/g). The obtained pellets were formed into 1.2 mm thick sheetsand 100 micrometer thick sheets with the press molding machine (at 220°C.). The various physical properties of the sheet were mearured. Theresults are summarized in Table 2.

COMPARATIVE EXAMPLE 9

The pellets of the thermoplastic elastomer were prepared as in Example12 except that 180° C. parts by weight of polyethylene glycol having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,was employed as the polyether compound (a) together with 120 parts ofpolytetramethylene glycol having the number-average molecular weight of1,000, the acid value and the hydroxyl value of 0 (micro-eq/g) and 2,000(micro-eq/g) respectively and 87.5 parts of 4,4′-diphenylmethanediisocyanate having the NCO value of 8,000 (micro-eq/g). The obtainedpellets were formed into 1.2 mm thick sheets and 100 micrometer thicksheets with the press molding machine (at 230° C.). The various physicalproperties of the sheet were measured. The results are summarized inTable 2.

COMPARATIVE EXAMPLE 10

The pellets of the thermoplastic elastomer were prepared as in Example12 except that all of the polyether compound (a), the polyester compound(b), and the poly-isocyanate compound (c) were blended simultaneouslyand led through the first barrel, but only as clay-like product wasobtained without the thermoplastic elastomer of the present inbentionobtained. The thermoplastic elastomer according to the present inventionwas not obtained.

TABLE 2 Example 12 13 14 15 16 17 18 19 20 21 22 Thermoplastic elastomerContent of polyether 65 64 65 65 73 55 63 64 73 54 61 component (wt %)C/O ratio for 2 2 2.4 2.3 2 2 2 2 2 2 2 polyether component Glasstransition −30 −30 −40 −45 −45 −25 −42 −30 −30 −30 −30 temperature (°C.) Physical Property of Thermoplastic elastomer Melting point (° C.)183 188 183 185 172 184 155 158 147 153 158 Surface rigidity (JIS A) 7273 72 72 67 88 91 72 65 88 75 Tensile strength (kgf/cm2) 200 170 220 200160 280 100 170 150 180 155 Elongation (%) 1200 1000 1300 1100 1400 900650 1200 1400 1500 1600 Permanent strain of 58 50 58 59 59 53 98 75 8170 74 Compression (100° C., %) Moisture permeability (g/cm2/24 hr) 90008500 7000 6800 10000 6000 10200 8200 800 7800 8600 (ASTM F372-73)Moisture permeability (g/cm2/24 hr) 3700 3600 3400 3400 3800 3300 38003600 3600 3500 3600 (JIS Z0208) Yellowing value for light resistance 4 55 2 4 3 4 3 5 4 3 Surface rigidity for light resistance 74 73 72 73 6888 89 73 66 88 76 (JIS A) Solubility x x x x ∘ Δ ∘ ∘ ∘ ∘ ∘ Stability x xx x Δ x Δ ∘ ∘ ∘ ∘ Comparative example 6 7 8 9 10 Thermoplastic elastomerContent of polyether 29 62 58 62 62 component (wt %) C/O ratio for 2 4 22.8 2 polyether component Glass transition −20 −50 −10 −47 — temperature(° C.) Physical Property of Thermoplastic elastomer Melting point (° C.)200 185 180 185 Surface rigidity (JIS A) 98 75 80 75 Tensile strength(kgf/cm2) 350 220 350 230 Elongation (%) 600 1400 700 1350 Permanentstrain of 50 54 55 55 Compression (100° C., %) Moisture permeability(g/cm2/24 hr) 2000 1000 2500 3500 (ASTM F372-73) Moisture permeability(g/cm2/24 hr) 1100 600 1400 1800 (JIS Z0208) Yellowing value for lightresistance 25 30 25 28 Surface rigidity for light resistance 99 79 83 78(JIS A) Solubility x x x x Stability x x x x

EXAMPLE 23

The pellets of thermoplastic elastomer obtained in the example 1 weredried in an oven at 80° C. for 10 hours, and spun on the method of meltspinning by using an ordinary melt spinning machine under condition of aspinning temperature of 210° C., a spinning speed of 600 m/min, and anout-put of molten polymer of 40 g/min, obtaining an non-drawn yarn of600 denier/10 F. The non-drawn yarn was drawn at a drawing speed of 200m/min with a drawing ration of 3.0. Then it was passed over a heat plateof 120° C. for a heat shrinkage of 50%, finally yielding an elastomerfiber made of a thermoplastic elastomer.

A fabric having the weight of 50 g/m² was woven from an elastomer fibermentioned hereinabove. The woven fabric was evaluated by the followingtesting method. The results are shown in Table 3.

Water Absorption Ratio:

The fabric was cut to a piece of 10 cm by 10 cm as a test sample, andleft under an atmosphere of 50% relative humidity (RH) and at 23° C. for24 hours. The measured weight of a test sample after leaving under anatomospere of 50% (RH) and at 23° C. for 24 hours mentioned hereinabovewas assumed to the initial weight (W0). Then the test piece was soakedin distilled water at 23° C. for 10 hours. It was measured of the weight(W1) after removing the excess water by a filter paper.

-   -   Water absorption ratio (%)=W1/W0×100        Moisture-Releasing Character or Drying Time: The test piece used        in the above measurement was left in an apparatus for the        measurement of drying time at 23° C. under an atmosphere of 50%        relative humidity, and measured of the time for drying        naturally.

EXAMPLE 24

A fabric having the weight of 50 g/m² was woven using 50 weight % of theelastomer yarn made of the thermoplastic elastomer obtained in theexample 23 and 50 weight % of a commercial elastomer yarn made of etherpolyurethane (ESPA produced by Toyobo, 70 denier). The woven fabric wasevaluated similar to the example 23. The results are shown in Table 3.

COMPARATIVE EXAMPLE 11

A fabric having the weight of 50 g/m² was woven using a commercialelastomer yarn made of ether polyurethane (ESPA; product of Toyobo in 70denier). It was evaluated similar to the example 23. The results areshown in Table 3.

TABLE 3 Water absorption Drying time ratio (%) (min) Example 23 150 100Example 24 80 90 Comparative example 11 10 110

EXAMPLE 25

An elastomer composition comprising 300 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,000, the acid value and thehydroxyl value of 0 (micro-eq/g) and 2,000 (micro-eq/g) respectively,87.5 parts of 4,4′-diphenylmethane diisocyanate, which corresponds tothe poly-isocyanate compound (c) having the NCO value of 8,000(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the above-mentioned polyester (b-1) through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolten and mixed together at 200° C. The product in pellet form was thethermoplastic elastomer of the present invention.

Production of Elastomer Film:

The obtained elastomer composition was dried at 80° C. for 8 hours, andmolded through the T-die molding method at 200° C. The out-put of moltenelastomer and the winding speed were adjusted so that the producedelastomer film became 30 micrometer thick. The molten elastomer wasextruded between two pieces of releasing paper, and wound up to a film.The moisture permeability of the film was evaluated.

Production of Laminated Sheet:

The obtained elastomer composition was dried at 80° C. for 8 hours, andmolded through the T-die molding method at 200° C. The out-put of moltenelastomer and the winding speed were adjusted so that the producedelastomer film became 30 micrometer thick. The molten elastomer wasextruded between a releasing paper and a non-woven fabric (Eltas E01050,product of Asahi Chemical Industries), and wound up to a laminatedsheet. The moisture permeability and the water-poof property of alaminated sheet were evaluated.

EXAMPLE 26

An elastomer composition comprising 1,000 parts (wt) of polyethyleneglycol, which corresponds to the polyether compound (a) having thenumber-average molecular weight of 1,500, the acid value and thehydroxyl value of 0 (micro-eq/g) and 1,330 (micro-eq/g) respectively,178.5 parts of 4,47-diphenylmethane diisocyanate, which corresponds tothe poly-isocyanate compound (c) having the NCO value of 8,000(micro-eq/g), was led into a bi-axial extruder (produced by ToshibaMachinery, L/D=58) through its first barrel, supplying at the same time100 parts of the polyester (b-1) mentioned hereinabove through the fifthbarrel of the same extruder using the compulsory side feeder, and wasmolded into a sheet through the bi-axial extruder with a T-die of 450 mmwidth directly after melting and mixing together at 200° C. The out-putof molten elastomer and the winding speed were adjusted so that theproduced elastomer film became 30 micrometer thick. The molten elastomerwas extruded between a releasing paper and a non-woven fabric (EltasE01050, product of Asahi Chemical Industries), and wound up to alaminated sheet. The moisture permeability and the water-poof propertyof the sheet were evaluated.

The physical property was evaluated as shown below.

Waterproof Property:

A test piece of the resin-laminated fabric was pot on one side of openend of a glass tube (inner diameter 40 mm, height 1,000 mm) using asealing material. The glass tube was placed vertically on a filter paperwith the side of fabric-puton surface downward. Colored water was pouredinto the glass tube and kept for 24 hours. Then the filter paper waschecked for coloration. If not colored, the test piece was judged tohave the waterproof property.

COMPARATIVE EXAMPLE 12

In the example 26, pelletization of the obtained elastomer was tried.But moldable pellets were not obtained due to stickiness of the pellets.

TABLE 4 Moisture permeability g/m2/day Waterproofing (JIS Z 0208)Property Example 25 (film) 12,000 — Example 25 11,000 Positive(laminated sheet) Example 26 18,000 Positive (laminated sheet)Comparative example 12 Not moldable

EXAMPLE 27

Production of Polyester (b)

A reaction system comprising 100 parts of dimethyl terephthalate, 102parts of 1,4-butane diol, 12 parts of polytetramethylene glycol havingthe number-average molecular weight of 650 (product of BASF, PTHF650),0.06 parts of tetrabutyl titanate as catalyst, 0.01 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.01 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 1 hour under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed measuring the amount of refluxing methanol. After thecompletion of the ester-exchange reaction, the reaction mixture washeated further to 240° C. reducing the pressure. The system was kept for40 minutes for the polycondensation reaction, yielding finally 37 parts(wt) of the ester copolymer of white color.

Production of the Thermoplastic Elastomer Composition:

An elastomer composition comprising 100 parts of polyethylene glycolhaving the number-average molecular weight of 1,000 and 22 parts of4,4′-diphenylmethane diisocyanate was led into a bi-axial extruder(produced by Belstorf Company, L/D=25), and mixed together at 200° C.(residence time 200 sec) yielding a prepolymer. Then 22 parts of theabove molten ester copolymer were blended with the prepolymer mentionedhereinabove at 180° C., yielding a thermoplastic elastomer composition.

Production of Resin-Laminated Fabric:

The elastomer composition mentioned hereinabove was dried at 80° C. forseveral hours and was molded through the T-die molding method into afilm, which was laminated with a non-woven polyester fabric (product ofAsahi Chemical Industries, EstalE0015) while the molded film stillremained to be thermo-adhesive. The film laminated with a non-wovenpolyester fabric was pressed between the laminating rolls, and wound upto a resin-laminated fabric.

The obtained resin-laminated fabric was evaluated of its moisturepermeability, waterproofing property, and dewing property.

EXAMPLE 28

Production of Polyester (b):

A reaction system comprising 100 parts of dimethyl terephthalate, 102parts of 1,4-butane diol, 0.06 parts of tetrabutyl titanate as catalyst,0.01 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.01 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 1 hour under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed measuring the amount of refluxing methanol.

After the completion of the ester-exchange reaction, the reactionmixture was heated further to 240° C. reducing the pressure. The systemwas kept for 25 minutes for the polycondensation reaction, yieldingfinally 35 parts of the ester copolymer of white color.

Production of the Thermoplastic Elastomer Composition:

An elastomer composition comprising 100 parts of polyethylene glycolhaving the number-average molecular weight of 1,500 and 29 parts of4,4′-diphenylmethane diisocyanate was led into a bi-axial extruder(produced by Belstorf Company, L/D=25), and mixed together at 200° C.yielding a prepolymer. Then 22 parts of the above molten ester copolymerwere blended with the prepolymer mentioned hereinabove at 180° C.yielding a thermoplastic elastomer composition.

Production of Moisture Permeable Waterproofing Fabric:

The above elastomer composition was dried at 80° C. for several hoursand was molded through the T-die molding method into a film, which waslaminated with a non-woven polyurethane fabric (product of Kanebo,Espansione) while the molded film still remained to be thermo-adhesive.The film laminated with a nono-woven polyurethane fabric was pressedbetween the laminating rolls, and wound up to a resin-laminated fabric.The obtained resin-laminated fabric was evaluated of its propertiessimilar to example 27. The results are shown in Table 5.

EXAMPLE 29

Production of Polyester (b)

34 parts by weight of the ester copolymer was prepared as in Example 28except that the time for polycondensation was 40 minutes.

Production of the Thermoplastic Elastomer Composition:

An elastomer composition comprising 100 parts (wt) of polyethyleneglycol having the number-average molecular weight of 1,000, 25 parts ofpolytetramethylene glycol, and 27 parts of 4,4′-diphenylmethanediisocyanate was led into a bi-axial extruder (produced by BelstorfCompany, L/D=25); and mixed together at 200° C. (residence time 200 sec)yielding a prepolymer. Then 27 parts of the molten ester copolymermentioned hereinabove were blended with the prepolymer mentionedhereinabove at 180° C. yielding a thermoplastic elastomer composition.

Production of Moisture Permeable Waterproof Fabric:

The above elastomer composition was dried at 80° C. for several hoursand was molded through the T-die molding method into a film, which waslaminated with a non-woven polyester fabric(0.29 mm thick) while themolded film still remained to be thermo-adhesive. The film laminatedwith a non-woven polyester fabric was pressed between the laminatingrolls, and woven up to a resin-laminated fabric.

The obtained resin-laminated fabric was evaluated of its propertiessimilar to example 27. The results are shown in Table 5.

COMPARATIVE EXAMPLE 13

The thermoplastic elastomer composition was prepared in Example 28except that polytetramethylene glycol was employed instead ofpolyethylene glycol.

COMPARATIVE EXAMPLE 14

The polyester (b) was prepared as in Example 27 except that the time forpolycondensation was set to 150 minutes instead of 40 minutes. But thethermoplastic elastomer composition was not obtained.

COMPARATIVE EXAMPLE 15

A commercial urethane elastomer was dried at 80° C. for several hoursand was molded through the T-die molding method into a film, which waslaminated with anon-woven polyester fabric of a similar type used in theexample 27 while the molded film still remained to be thermo-adhesive.The film laminated with a non-woven polyester fabric was pressed betweenthe laminiating rolls, and woven up to a resin-laminated fabric. Theobtained resin-laminated fabric was evaluated of its properties similarto example 27. The results are shown in Table 5.

TABLE 5 Composition of Thermoplastic Elastomer Polyether (a) carbon/Number- Glass oxygen average transition Polyester atomic Moleculartemperature (b) Ratio weight Species (° C.) Example 27 1,000 2 1,000 PEG−30 Example 28 800 2 1,500 PEG −35 Example 29 1,000 2.4 1,000 PEG/ −36PTMG Comp. 800 4 1,000 PEG −40 Example 13 Comp. 24,000 2 1,000 PEG —Example 14 Comp. — — — — −18 Example 15Performance of Moisture Permeable Waterproof Fabric

Moisture Moisture permeability Dewing permeability (g/m2/day) Waterproofproperty (g/m2/day) (ASTM F372-73) Property (g) (JIS Z0208) Example 278,700 Positive 0.3 3,600 Example 28 15,800 Positive 0.1 4,500 Example 296,200 Positive 0.3 3,300 Comp. 1,300 Positive 1.2 700 Example 13 Comp. —— — — Example 14 Comp. 2,600 Positive 0.7 1,500 Example 15

The properties of the product were measured on the following methods.

Glass Transition Temperature:

Measured according to the aforementioned method described in this patentspecification.

Dewing Property:

A glass container containing water of 40° C. was covered with a testpiece of the resin-laminated fabric so that its resin surface comes toinside. It was left for 1 hour in an apparatus having constanttemperature and humidity that kept the temperature at 10° C. and therelative humidity at 60%. Then drops of dew attached on the surface weremeasured of the weight. The dewing property was determined on theweight.

EXAMPLE 30

The sheets obtained in the example 1 through 11 and the comparativeexamples 1 through 4 were tested for the resistance to sterilization andthe ease of sterilization. The results are summarized in Table 6.

TABLE 6 Comparative Example Example 1 2 3 4 5 6 7 8 9 10 11 1 2 3 4Anti-sterilization Tensile strength (kgf/cm2) 180 165 210 190 145 275 90145 130 170 140 345 200 325 200 Elongation (%) 1,100 1,000 1,200 1,0501,200 900 600 1,000 1,800 1,300 1,450 550 1,200 600 1,200 Ease of ∘ ∘ ∘∘ ∘ ∘ ∘ ∘ ∘ ∘ ∘ x x x x SterilizationResistance to Sterilization (Anti-Sterilization):

A 2 mm thick test sheet was treated for sterilization under anatmosphere of 121° C. and high-pressured steam at a pressure (gauge) oflatm, for 60 minutes. Then it was cooled to room temperature, andmeasured of the tensile characteristics by the following method.

Tensile Characteristics:

The tensile strength and tensile elongation were measured at roomtemperature according to the method of JIS K6301.

Ease of Sterilization:

Bacillus Stearothermophilus was cultured with Muller Hinton Broth at 35°C. for about 20 hours until the number of the bacillus reached 10⁴/ml. Adrop of the solution was fallen on a filter paper of 1 cm². The filterpaper was dried in the air and wrapped up with a 100 micrometer thickfilm achieving an airtight state. Then it was treated for high-pressuredsteam sterilization at 121° C., 1 atm for 20 minutes. After thesterilization, the filter paper was left on a Muller Hinton Ager andcultured at 35° C. for about 20 hours. Then the growth of the bacilluswas checked. The simbol X was given on a case when the growth of thebacillus was confirmed, and the simbol ◯ on a case not confirmed.

EXAMPLE 31

The sheets obtained in the example 1 through 7, the comparative examples1 through 5 and the comparative example 16 were tested for thewater-swelling degree per weight (%) and the modulus of elasticity atstored state/Pa (at 40° C.). The results are summarized in Table 7.

COMPARATIVE EXAMPLE 16

A commercial thermoplastic elastomer (polyurethane elastomer AM3P9029,product of Nippon Miractolan) was formed with the press moldingmachine(at 200° C.) into 2 mm thick sheets and 100 micrometer thicksheets. The various physical properties of the sheets were measured.

TABLE 7 Water Modulus of absorption elasticity ratio/ at stored state wt(%) (40° C.)/Pa Example 1 80 7.0 × 10⁶ Example 2 77 7.2 × 10⁶ Example 355 7.0 × 10⁶ Example 4 65 7.0 × 10⁶ Example 5 110 3.0 × 10⁶ Example 6 6012.5 × 10⁶  Example 7 75 7.5 × 10⁶ Comp. Example 1 20 30.0 × 10⁶  Comp.Example 2 3 7.0 × 10⁶ Comp. Example 3 60 8.0 × 10⁶ Comp. Example 4 157.0 × 10⁶ Comp. Example 5 Elastomer was not Obtained Comp. Example 16 5530.0 × 10⁶ 

The storage modulus of elasticity and water absorption ratio in Table 7were measured under the following conditions.

Storage Modulus of Elasticity:

Apparatus: RSA-II, produced by Rheometric Scientific Co. Ltd.

-   -   Temperature range: From −100° C. to 200° C.    -   Rate of temperature raising: 3° C./min    -   Employed frequency: 1.61 Hz    -   Distortion: 0.05%

Water Absorption Ratio for the Thermoplastic Elastomer:

{circle around (1)} A test sheet (50 mm×50 mm×1 mm) was completely driedin a desiccator with desiccant (silica gel). Then it was measured of theinitial weight (W0).

{circle around (2)} The test sheet was soaked in ion-exchanged water at23° C. for 24 hours. Then it was measured of the weight (W1).

{circle around (3)} Water absorption ratio=(W1−W0)/W0×100 (weight %).

EXAMPLE 32

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,102 parts of 1,4-butane diol, 12 parts of polytetramethylene glycolhaving the number-average molecular weight of 650 (product of BASF,PTHF650), 0.3 parts of tetrabutyl titanate as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed measuring the amount of refluxing methanol. After thecompletion of the ester-exchange reaction, the reaction mixture washeated under reducing condition of the pressure. The polymerizationsystem reached less than 2 mmHg at 240° C. in 20 minutes. As the result,120 parts (wt) of the polyester component (S) having the number-averagemolecular weight of 1,500 and white color were obtained.

A composition comprising 177.8 parts (wt) of polytetramethylene glycolhaving the number-average molecular weight of 1,000 (product of BASF,PTHF1000 and the glass transition temperature of −56° C.) as thepolymeric component (T) and 55.6 parts of 4,4′-diphenylmethanediisocyanate was led into a bi-axial extruder (produced by BelstorfCompany), and mixed together at 150° C. (residence time 200 sec). Then100 parts of the polyester component (S) mentioned hereinabove were putinto the extruder from its side feeder for the blending at 205° C.(residence time 200 sec) yielding pellets of the ester thermoplasticelastomer. The pellets were formed into 2 mm thick sheets through thepress molding machine(at 230° C.), and various physical properties ofthe sheets were measured. The results are summarized in Table 11.

EXAMPLE 33

A reaction system comprising 100 parts (wt) of dimethyl terephthalate,102 parts of 1,4-butane diol, 0.25 parts of tetrabutyl titanate ascatalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 3 hours under a nitrogen atmosphere for theester-exchange reaction. The proceeding extent of the reaction wasconfirmed measuring the amount of refluxing methanol. After thecompletion of the ester-exchange reaction, the reaction mixture washeated under reduced pressure. The polymerization system reached lessthan 5 mmHg at 240° C. in 20 minutes. As the result, 120 parts (wt) ofthe polyester component (S) having the number-average molecular weightof 1,200 and white color were obtained.

A composition comprising 562.5 parts (wt) of poly-1,2-propylene glycolhaving the number-average molecular weight of 3,000 (product of MitsuiChemical, PPG3000 and the glass transition temperature of −54° C.) asthe polymeric component (T) and 62.5 parts of 4,4′-diphenylmethanediisocyanate was led into a bi-axial extruder (produced by BelstorfCompany), and mixed together at 150° C. (residence time 200 sec). Then100 parts of the polyester component (S) mentioned hereinabove were putinto the extruder from its side feeder for the blending at 210° C.(residence time 200 sec), yielding pellets of the ester thermoplasticelastomer. The pellets were formed into 2 mm thick sheets through thepress molding machine(at 230° C.), and various physical properties ofthe sheets were measured. The results are summarized in Table 11.

COMPARATIVE EXAMPLE 21

A composition comprising 100 part (wt) of the polyester component (S)employed in the example 33 and 562.5 parts of poly-1,2-propylene glycolhaving the number-average molecular weight of 3,000 (product of MitsuiChemical, PPG3000 and the glass transition temperature of −54° C.) wasled into a bi-axial extruder (produced by Belstorf Company) and moltenat 150° C. (residence time 200 sec). Then 62.5 parts of4,4′-diphenylmethane diisocyanate were led into the bi-axial extruder bypressurization and mixed together at 210° C. (residence time 400 sec).But the thermoplastic elastomer was not obtained.

TABLE 11 Comp. Example Example Example 32 33 21 Glass transitiontemperature −48 −44 — Tg (° C.) Melting point (° C.) 202 191 — Surfacerigidity (JIS A) 84 69 — Modulus of tensile  23° C. 19.4 3.5 —elasticity (E′) 150° C. 9.9 1.2 — 10⁶ Pa Tensile Tensile 310 280 —Characteristics strength kgf/cm2 Elongation % 1,400 1,600 — Permanentcompression strain 61 68 — (100° C.) %

Because the thermoplastic elastomer was not obtained, the columns forthis comparative example 21 in Table 11 are vacant.

A reaction system comprising 128 parts (wt) of hexamethylene diamine,146 parts of adipic acid, 0.3 parts of phosphoric acid as catalyst, 0.3parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 260° C. for 20 minutes under a nitrogen atmosphere for thepolycondensation reaction, yielding 238 parts of the polyamide component(P) having the number-average molecular weight of 1,500 and white color.

A composition comprising 177.8 part (wt) of the polytetramethyleneglycol having the number-average molecular weight of 1,000 (product ofBASF, PTHF1000 and the glass transition temperature of −56° C.) as thepolymeric component (T) and 55.6 parts of 4,4′-diphenylmethanediisocyanate was led into a bi-axial extruder (produced by BelstorfCompany) and was mixed together at 150° C. (residence time 200 sec).Then 100 parts of the polyamide component (P) mentioned hereinabove werecompletely molten and led into the bi-axial extruder from its sidefeeder and was further mixed together at 255° C. (residence time 200sec). The product finally obtained was a pellet of the amide elastomer.The pellets were formed into 2 mm thick sheets through the press moldingmachine (at 260° C.), and various physical properties of the sheets weremeasured. The results are summarized in Table 12.

EXAMPLE 35

A reaction system comprising 100 parts of ε-caprolactam, 0.25 parts ofphosphoric acid as catalyst, 0.3 parts of1,3,5-trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)-benzene and0.3 parts of tris(2,4-di-t-butyl-phenyl)-phosphite as stabilizers washeated at 200° C. for 20 minutes under a nitrogen atmosphere for thering-opening polymerization reaction. Then an excess amount ofhexamethylene diamine was added to the system heating further at 200° C.for 3 hours. After the excess hexamethylene diamine was removed byreduced pressure, 120 parts of polyamide component (P) having thenumber-average molecular weight of 1,200 and white color were obtained.

A composition comprising 562.5 part of the poly-1,2-propylene glycolhaving the number-average molecular weight of 3,000 (product of MitsuiChemical, PPG3000) and the glass transition temperature of −54° C. asthe polymeric component (T) and 62.5 parts of 4,4′-diphenylmethanediisocyanate was led into a bi-axial extruder (produced by BelstorfCompany) and was mixed together at 150° C. (residence time 200 sec).Then 100 parts of the above polyamide component (P) mentionedhereinabove were completely molten and led into the bi-axial extruderfrom its side feeder and was further mixed together at 215° C.(residence time 200 sec). The product finally obtained was a pellet ofthe amide elastomer. The pellets were formed into 2 mm thick sheetsthrough the press molding machine (at 230° C.), and various physicalproperties of the sheets were measured. The results are summarized inTable 12.

COMPARATIVE EXAMPLE 22

A composition comprising 100 part (wt) of the polyamide component (p)employed in the example 35 and 562.5 parts of poly-1,2-propylene glycolhaving the number-average molecular weight of 3,000 (product of MitsuiChemical, PPG3000 and the glass transition temperature of −54° C.) wasled into a bi-axial extruder (produced by Belstorf Company) and wasmolten. Then 62.5 parts of 4,4′-diphenylmethane diisocyanate were ledinto the bi-axial extruder by pressurization and was mixed together at215° C. (residence time 400 sec). But the thermoplastic elastomer wasnot obtained.

TABLE 12 Comp. Example Example example 34 35 22 Glass transitiontemperature −48 −44 — Tg (° C.) Melting point (° C.) 247 211 — Surfacerigidity (JIS A) 83 67 — Modulus of tensile  23° C. 18.7 3 — elasticity(E′) 150° C. 10.8 1.5 — 10⁶ Pa Tensile Tensile 380 320 — Characteristicsstrength kgf/cm2 Elongation % 1,500 1,700 — Permanent compression strain58 63 — (100° C.) %

Because the thermoplastic elastomer was not obtained, the columns forthis comparative example 22 in Table 12 are vacant.

The physical properties in the Table 11 and Table 12 were measured bythe following methods:

(1)Glass Transition Temperature (Tg) and the Melting Point

Measured on a DSC (differential scanning calorimeter) with a rate oftemperature raising at 10° C./min.

(2)Surface Rigidity

Measured with the A-type spring at 23° C. according to the method of JISK6301.

(3)Modulus of Tensile Elasticity (E′)

Measured of the dynamic viscoelasticity spectra at 10 Hz changing thetemperature, and calculated from the E′ values at room temperature (23°C.) and a high temperature (150° C.).

(4)Tensile Characteristics

Measured of the tensile strength and the tensile elongation at 23° C.according to the method of JIS K6301.

(5)Permanent Compression Strain

Measured at 100° C. with 25% distortion according to the method of JISK6301.

From these results it is apparent that the production method of theester elastomer according to the part II (1) of the present inventioncomprises the composition mentioned hereinabove and facilitatesproduction of a ester elastomer rich in the block property in itspolyester component. As a result, the invention presents an esterelastomer that has excellent elasticity and mechanical properties at ahigh temperature simultaneously.

Also it is apparent that the production method of the amide elastomeraccording to the part II (3) of the present invention comprises thecomposition mentioned hereinabove and facilitates production of an amideelastomer rich in the block property in its polyamide component. As aresult, the present invention presents an amide elastomer that hasexcellent elasticity and mechanical properties at a high temperaturesimultaneously.

INDUSTRIAL APPLICABILITY

The present invention presents a thermoplastic elastomer that exhibitshigh affinity to water, excellent molecular movement and superiormoisture permeability. According to the present invention, it ispossible to obtain a thermoplastic elastomer that exhibits high affinityto water, excellent molecular movement property, superb block propertyof its short-chain polyester component, and outstanding moisturepermeability as well as excellent elasticity and mechanical propertiesat a high temperature simultaneously. Also the present inventionfacilitates production of a thermoplastic elastomer that has excellentsolution painting characteristics by copolymerizing a short-chainpolyester component. Furthermore, the present invention facilitatesproduction of a thermoplastic elastomer that has excellent resistance tolight by employing an isocyanate component comprising aliphatic group,cycloaliphatic group, or isocyanate group in which the aromatic group isnot directly bonded with.

The presesnt invention presents an elastomer fiber and fabric havingexcellent water absorption characteristics, excellent moisturepermeability made of a thermoplastic elastomer that exhibits highaffinity to water and excellent molecular movement.

According to the present invention, it is possible to obtain athermoplastic elastomer that exhibits high affinity to water, excellentmolecular movement property, superb block property for its short-chainpolyester component, and outstanding moisture permeability as well asexcellent elasticity and mechanical properties at a high temperaturesimultaneously.

Films and sheets produced according to the present invention areequipped with excellent moisture permeability and water-proof propertyat the same time.

According to the present invention, it is possible to obtain a moldedproduct for medical treatment, which comprises a thermoplastic elastomerhaving excellent flexibility, heat resistance, anti-sterilizationproperty, and ease of steam sterilization, wherein the thermoplasticelastomer is characterized by high affinity to water, excellentmolecular movement property, superb block property for its short-chainpolyester component, and outstanding moisture permeability as well asexcellent elasticity and mechanical properties at a high temperaturesimultaneously.

The present invention presents a thermoplastic elastomer that exhibitshigh affinity to water, excellent molecular movement and superiormoisture permeability. According to the present invention, it ispossible to obtain a thermoplastic elastomer that exhibits high affinityto water, excellent molecular movement property, superb block propertyfor its short-chain polyester component, and oustanding moisturepermeability as well as excellent elasticity and mechanical propertiesat a high temperature simultaneously.

1. A thermoplastic elastomer, which comprises, as a constituting unit, apolyether component (A) and a polyester component (B), wherein thepolyether component (A) comprises poly-oxyalkylene groups(—C_(n)H_(2n)O—) having a carbon/oxygen atomic ratio in a range from 2.0to 2.5, the polyester component (B) has a number-average molecularweight in a range from 500 to 10,000 and comprises polybutyleneterephthalate in an amount of 40 to 90 weight %, the thermoplasticelastomer has a content of polyether component (A) in a range from 50 to95 weight %, and the thermoplastic elastomer has a glass transitiontemperature of not more than −20° C.
 2. A thermoplastic elastomer asclaimed in claim 1, wherein the polyether component (A) is bonded with apoly-isocyanate component (C).
 3. A thermoplastic elastomer as claimedin claim 1, wherein the polyether component (A) has a number-averagemolecular weight in a range from 500 to 5,000.
 4. A thermoplasticelastomer as claimed in claim 1, wherein the polyether component (A)comprises a polyethylene glycol component.
 5. A thermoplastic elastomeras claimed in claim 1, wherein the polyester component (B) comprises 50to 100 weight % of a short-chain polyester component represented by thefollowing formula (1) and 50 to 0 weight % of a long-chain polyestercomponent represented by the following formula (2):—CO—R₁—CO—O—R₂—O—  (1) wherein R₁ is (i) a divalent aromatic hydrocarbongroup of 6 to 12 carbon atoms and/or (ii) a divalent alkylene group of 2to 10 carbon atoms, or a divalent cycloaliphatic hydrocarbon group of 6to 12 carbon atoms; R₂ is an alkylene group of 2 to 8 carbon atomsand/or a divalent cycloaliphatic radical of 6 to 12 carbon atoms;—CO—R₃—CO—O—R₄—  (2) wherein R₃ is (i) a divalent aromatic hydrocarbongroup of 6 to 12 carbon atoms and/or (ii) a divalent alkylene group of 2to 10 carbon atoms or a divalent cycloaliphatic hydrocarbon group of 6to 12 carbon atoms; R₄ is a repeating unit of —R₅—O—, and R₅ is analkylene group of 2 to 8 carbon atoms.
 6. A thermoplastic elastomer asclaimed in claim 1, wherein the polyester component (B) comprises adicarboxylic acid component having a molar ratio of aromaticdicarboxylic acid groups to aliphatic dicarboxylic acid groups in arange from 100:0 to 40:60.
 7. A thermoplastic elastomer as claimed inclaim 1, wherein the polyester component (B) comprises a diol componenthaving a molar ratio of linear aliphatic diol groups to cycloaliphaticdiol groups in a range from 100:0 to 40:60.
 8. A thermoplastic elastomeras claimed in claim 2, wherein the poly-isocyanate component (C)comprises (i) an aliphatic poly-isocyanate component, (ii) acycloaliphatic poly-isocyanate component or (iii) a poly-isocyanatecomponent in which the isocyanate group is not directly bonded to anaromatic ring.
 9. A thermoplastic elastomer as claimed in claim 2,wherein the poly-isocyanate component (C) comprises a diisocyanatecomponent represented by the following formula (3):—O—CO—NH—R₆—NH—CO—O—  (3) wherein R₆ is an alkylene group of 2 to 15carbon atoms, a divalent cycloaliphatic hydrocarbon group, a phenylenegroup, a methylene group, or a composite radical of alkylene group andphenylene group.
 10. A thermoplastic elastomer, which comprises, as aconstituting unit, a polyether component (A) and a polyester component(B), wherein: 1) the thermoplastic elastomer has a water absorptionratio in a range from 50 to 200 weight %, 2) the thermoplastic elastomerhas a storage modulus of elasticity at 40° C. in a range from 1×10⁶ Paand 25×10⁶ Pa, 3) the thermoplastic elastomer has a glass transitiontemperature of not more than −20° C., and (4) the polyester component(B) has a number-average molecular weight in a range from 500 to 10,000and comprises polybutylene terephthalate in an amount of 40 to 90 weight%.
 11. A thermoplastic elastomer as claimed in claim 10, wherein thepolyether component (A) comprises poly-oxyalkylene groups(—C_(n)H_(2n)O—) having a carbon/oxygen atomic ratio in a range from 2.0to 2.5, the thermoplastic elastomer has a content of polyether component(A) in a range from 50 to 95 weight %, and the thermoplastic elastomerhas a glass transition temperature of not more than −20° C.
 12. A methodfor producing a thermoplastic elastomer as claimed in claim 1 or 10,which comprises producing a prepolymer by reacting a polyether compound(a) with a poly-isocyanate compound (c), and then reacting theprepolymer with a polyester compound (b).
 13. A fiber, comprising athermoplastic elastomer as claimed in claim 1 or
 10. 14. A fabriccomprising a fiber as claimed in claim
 13. 15. An elastomer film orsheet, comprising a thermoplastic elastomer as claimed in claim 1 or 10.16. A method for producing an elastomer film or sheet according to claim15, which comprises producing a prepolymer by reacting a polyethercompound (a) and a poly-isocyanate compound (c), reacting the prepolymerwith a polyester compound (b) to form a reaction product, and moldingcontinuously the reaction product.
 17. A moisture permeablewaterproofing fabric, which is produced by laminating a fabric on atleast one side of the elastomer film or sheet as claimed in claim 15.18. A fabric, wherein at least one side of the fabric is coated with acomposition containing the thermoplastic elastomer as claimed in claim 1or
 10. 19. A moisture permeable waterproofing fabric as claimed in claim17, wherein said fabric comprises an elastomer fiber.
 20. An elastomerfilm or sheet as claimed in claim 15, having a moisture permeability ofnot less than 2,000 g/m² (24 hr).
 21. An article of manufacture,comprising a moisture permeable waterproofing fabric as claimed in claim17.
 22. A molded medical product, obtained by molding the thermoplasticelastomer as claimed in claim
 1. 23. A moisture permeable waterproofingfabric as claimed in claim 17, having a moisture permeability not lessthan 2,000 g/m² (24 hr).
 24. An article of manufacture as claimed inclaim 21, which is a fabric, tent or shoe.